| Tuesday, April 5 |
| » Lost to Dodgers (1-0), 16-7 | Astrodome (0-1) | 0-1 | |
| » W: Alejandro Pena (1-0) L: Frank LaCorte (0-1) S: Dave Stewart (1) | Second | 1 out |
| » Major-league debuts: Mike Madden and Julio Solano (Astros) |
| Wednesday, April 6 |
| » Lost to Dodgers (2-0), 4-2 | Astrodome (0-2) | 0-2 | Lost 2 |
| » W: Jerry Reuss (1-0) L: Dave Smith (0-1) S: Steve Howe (1) | Third | 2 out |
| Thursday, April 7 |
| » Lost to Pirates (2-0), 3-2 | Astrodome (0-3) | 0-3 | Lost 3 |
| » W: Rod Scurry (1-0) L: Bob Knepper (0-1) | Fourth | 2½ out |
| Friday, April 8 |
| » Lost to Pirates (3-0), 5-3 | Astrodome (0-4) | 0-4 | Lost 4 |
| » W: Rod Scurry (2-0) L: Frank DiPino (0-1) S: Jim Bibby (1) | Third | 2½ out |
| Saturday, April 9 |
| » Lost to Pirates (4-0), 1-0 | Astrodome (0-5) | 0-5 | Lost 5 |
| » W: Larry McWilliams (1-0) L: Joe Niekro (0-1) | Fourth | 3½ out |
| Sunday, April 10 |
| » Lost to Pirates (5-0), 10-8 | Astrodome (0-6) | 0-6 | Lost 6 |
| » W: Jim Bibby (1-0) L: Julio Solano (0-1) S: Rod Scurry (1) | Fifth | 4½ out |
| » Major-league debuts: Jim Winn (Pirates) |
| Monday, April 11 |
| » Lost to Dodgers (4-2), 4-3 | Dodger Stadium (0-1) | 0-7 | Lost 7 |
| » W: Steve Howe (1-0) L: Julio Solano (0-2) | Fifth | 5½ out |
| Tuesday, April 12 |
| » Lost to Dodgers (5-2), 3-1 | Dodger Stadium (0-2) | 0-8 | Lost 8 |
| » W: Alejandro Pena (2-0) L: Vern Ruhle (0-1) S: Steve Howe (2) | Fifth | 6½ out |
| » Major-league debuts: John Mizerock (Astros) |
| Wednesday, April 13 |
| » Lost to Dodgers (6-2), 5-3 | Dodger Stadium (0-3) | 0-9 | Lost 9 |
| » W: Pat Zachry (1-0) L: Frank LaCorte (0-2) | Sixth | 7½ out |
| Friday, April 15 |
| » Defeated Expos (5-3), 7-6 | Astrodome (1-6) | 1-9 | |
| » W: Bill Dawley (1-0) L: Ray Burris (0-1) | Sixth | 7 out |
| » Major-league debuts: Bill Dawley (Astros) |
| Saturday, April 16 |
| » Lost to Expos (6-3), 2-0 | Astrodome (1-7) | 1-10 | |
| » W: Charlie Lea (2-0) L: Bob Knepper (0-2) | Sixth | 7½ out |
| Sunday, April 17 |
| » Defeated Expos (6-4), 6-3 | Astrodome (2-7) | 2-10 | |
| » W: Nolan Ryan (1-0) L: Bill Gullickson (1-2) S: Vern Ruhle (1) | Sixth | 7 out |
| Tuesday, April 19 |
| » Defeated Reds (8-5), 6-5 | Astrodome (3-7) | 3-10 | Won 2 |
| » W: Bill Dawley (2-0) L: Tom Hume (0-1) | Fourth | 6½ out |
| Wednesday, April 20 |
| » Lost to Reds (9-5), 6-4 | Astrodome (3-8) | 3-11 | |
| » W: Rich Gale (2-0) L: Mike LaCoss (0-1) S: Ted Power (1) | Sixth | 7 out |
| Thursday, April 21 |
| » Defeated Reds (9-6), 4-3 | Astrodome (4-8) | 4-11 | |
| » W: Frank LaCorte (1-2) L: Tom Hume (0-2) | Sixth | 6½ out |
| Friday, April 22 |
| » Lost to Phillies (8-4), 6-3 | Astrodome (4-9) | 4-12 | |
| » W: Sid Monge (2-0) L: Nolan Ryan (1-1) S: Ron Reed (2) | Sixth | 7½ out |
| Saturday, April 23 |
| » Lost to Phillies (9-4), 7-3 | Astrodome (4-10) | 4-13 | Lost 2 |
| » W: John Denny (2-1) L: Joe Niekro (0-2) | Sixth | 8 out |
| Sunday, April 24 |
| » Defeated Phillies (9-5), 3-2 | Astrodome (5-10) | 5-13 | |
| » W: Mike Madden (1-0) L: Ron Reed (1-1) | Sixth | 8½ out |
| Tuesday, April 26 |
| » Defeated Expos (9-5), 2-0 | Stade Olympique (1-0) | 6-13 | Won 2 |
| » W: Bob Knepper (1-2) L: Bill Gullickson (1-3) | Fifth | 8½ out |
| Wednesday, April 27 |
| » Defeated Expos (9-6), 4-2 | Stade Olympique (2-0) | 7-13 | Won 3 |
| » W: Nolan Ryan (2-1) L: Scott Sanderson (3-1) S: Frank LaCorte (1) | Fifth | 7½ out |
| Friday, April 29 |
| » Defeated Phillies (10-7), 6-3 | Veteran's Stadium (1-0) | 8-13 | Won 4 |
| » W: Frank LaCorte (2-2) L: Steve Carlton (3-2) S: Bill Dawley (1) | Fifth | 7 out |
| Saturday, April 30 |
| » Lost to Phillies (11-7), 8-0 | Veteran's Stadium (1-1) | 8-14 | |
| » W: John Denny (3-1) L: Mike LaCoss (0-2) | Fifth | 7½ out |
| Sunday, May 1 |
| » Lost to Phillies (12-7), 11-3 | Veteran's Stadium (1-2) | 8-15 | Lost 2 |
| » W: Larry Christenson (1-2) L: Bob Knepper (1-3) | Fifth | 8½ out |
| Monday, May 2 |
| » Defeated Mets (6-13), 3-2 | Shea Stadium (1-0) | 9-15 | |
| » W: Nolan Ryan (3-1) L: Mike Torrez (1-3) S: Frank LaCorte (2) | Fifth | 8 out |
| » Major-league debuts: Jose Oquendo (Mets) |
| Tuesday, May 3 |
| » Defeated Mets (6-14), 7-4 | Shea Stadium (2-0) | 10-15 | Won 2 |
| » W: Joe Niekro (1-2) L: Craig Swan (1-2) S: Bill Dawley (2) | Fifth | 8 out |
| Wednesday, May 4 |
| » Defeated Mets (6-15), 4-3 | Shea Stadium (3-0) | 11-15 | Won 3 |
| » W: Mike LaCoss (1-2) L: Rick Ownbey (0-2) | Fifth | 7 out |
| Thursday, May 5 |
| » Lost to Braves (17-6), 6-3 | Atlanta-Fulton County Stadium (0-1) | 11-16 | |
| » W: Craig McMurtry (3-1) L: Bob Knepper (1-4) S: Steve Bedrosian (3) | Fifth | 8 out |
| Friday, May 6 |
| » Defeated Braves (17-7), 6-0 | Atlanta-Fulton County Stadium (1-1) | 12-16 | |
| » W: Frank DiPino (1-1) L: Phil Niekro (1-3) | Fifth | 7½ out |
| Saturday, May 7 |
| » Lost to Braves (18-7), 10-1 | Atlanta-Fulton County Stadium (1-2) | 12-17 | |
| » W: Pascual Perez (5-0) L: Joe Niekro (1-3) | Sixth | 8½ out |
| Sunday, May 8 |
| » Lost to Braves (19-7), 4-3 | Atlanta-Fulton County Stadium (1-3) | 12-18 | Lost 2 |
| » W: Rick Behenna (3-0) L: Mike LaCoss (1-3) S: Terry Forster (4) | Sixth | 9½ out |
| Monday, May 9 |
| » Defeated Mets (8-17), 6-4 | Astrodome (6-10) | 13-18 | |
| » W: Mike Madden (2-0) L: Rick Ownbey (0-3) S: Frank LaCorte (3) | Sixth | 9½ out |
| Tuesday, May 10 |
| » Defeated Mets (8-18), 5-4 | Astrodome (7-10) | 14-18 | Won 2 |
| » W: Frank DiPino (2-1) L: Neil Allen (0-4) | Fifth | 8½ out |
| Wednesday, May 11 |
| » Lost to Mets (9-18), 3-0 | Astrodome (7-11) | 14-19 | |
| » W: Tom Seaver (2-2) L: Mike Scott (0-1) | Sixth | 9 out |
| Thursday, May 12 |
| » Defeated Braves (20-10), 4-3 | Astrodome (8-11) | 15-19 | |
| » W: Frank DiPino (3-1) L: Pete Falcone (1-1) | Sixth | 9 out |
| Friday, May 13 |
| » Defeated Braves (20-11), 5-2 | Astrodome (9-11) | 16-19 | Won 2 |
| » W: Mike LaCoss (2-3) L: Rick Behenna (3-1) | Fifth | 8 out |
| Saturday, May 14 |
| » Lost to Braves (21-11), 4-3 | Astrodome (9-12) | 16-20 | |
| » W: Terry Forster (1-0) L: Bill Dawley (2-1) | Fifth | 9 out |
| Sunday, May 15 |
| » Lost to Braves (22-11), 9-4 | Astrodome (9-13) | 16-21 | Lost 2 |
| » W: Craig McMurtry (5-1) L: Bob Knepper (1-5) | Fifth | 10 out |
| Tuesday, May 17 |
| » Lost to Cardinals (18-12), 8-4 | Busch Stadium II (0-1) | 16-22 | Lost 3 |
| » W: Bob Forsch (3-3) L: Joe Niekro (1-4) | Sixth | 10 out |
| Wednesday, May 18 |
| » Lost to Cardinals (19-12), 9-5 | Busch Stadium II (0-2) | 16-23 | Lost 4 |
| » W: Joaquin Andujar (3-5) L: Frank DiPino (3-2) | Sixth | 11 out |
| Friday, May 20 |
| » Lost to Pirates (14-18), 4-3 | Three Rivers Stadium (0-1) | 16-24 | Lost 5 |
| » W: Larry McWilliams (4-3) L: Bob Knepper (1-6) S: Kent Tekulve (1) | Fifth | 11 out |
| Saturday, May 21 |
| » Defeated Pirates (14-19), 6-4 | Three Rivers Stadium (1-1) | 17-24 | |
| » W: Mike LaCoss (3-3) L: Randy Niemann (0-1) S: Frank DiPino (1) | Sixth | 10½ out |
| Monday, May 23 |
| » Defeated Cubs (14-23), 3-2 | Astrodome (10-13) | 18-24 | Won 2 |
| » W: Joe Niekro (2-4) L: Steve Trout (3-6) S: Frank DiPino (2) | Sixth | 11 out |
| Tuesday, May 24 |
| » Lost to Cubs (15-23), 5-4 | Astrodome (10-14) | 18-25 | |
| » W: Dick Ruthven (2-3) L: Mike Scott (0-2) S: Bill Campbell (3) | Sixth | 12 out |
| Wednesday, May 25 |
| » Defeated Cubs (15-24), 1-0 | Astrodome (11-14) | 19-25 | |
| » W: Mike Madden (3-0) L: Craig Lefferts (0-2) S: Bill Dawley (3) | Fifth | 12 out |
| Thursday, May 26 |
| » Lost to Cardinals (22-16), 5-3 | Astrodome (11-15) | 19-26 | |
| » W: Dave VonOhlen (1-0) L: Mike LaCoss (3-4) S: Bruce Sutter (4) | Fifth | 12 out |
| Friday, May 27 |
| » Lost to Cardinals (23-16), 3-1 | Astrodome (11-16) | 19-27 | Lost 2 |
| » W: Jeff Lahti (1-1) L: Bob Knepper (1-7) | Sixth | 12 out |
| Saturday, May 28 |
| » Defeated Cardinals (23-17), 9-2 | Astrodome (12-16) | 20-27 | |
| » W: Joe Niekro (3-4) L: John Martin (2-1) | Sixth | 12 out |
| Sunday, May 29 |
| » Lost to Cardinals (24-17), 7-3 | Astrodome (12-17) | 20-28 | |
| » W: Dave LaPoint (4-1) L: Mike Scott (0-3) | Sixth | 12 out |
| Monday, May 30 |
| » Defeated Cubs (17-27), 9-7 | Wrigley Field (1-0) | 21-28 | |
| » W: Bill Dawley (3-1) L: Bill Campbell (2-2) S: Frank DiPino (3) | Sixth | 12 out |
| Tuesday, May 31 |
| » Defeated Cubs (17-28), 12-10 | Wrigley Field (2-0) | 22-28 | Won 2 |
| » W: Frank LaCorte (3-2) L: Craig Lefferts (0-3) S: Dave Smith (1) | Sixth | 12 out |
| Wednesday, June 1 |
| » Lost to Cubs (18-28), 3-2 | Wrigley Field (2-1) | 22-29 | |
| » W: Chuck Rainey (5-4) L: Bob Knepper (1-8) S: Lee Smith (6) | Sixth | 13 out |
| Friday, June 3 |
| » Lost to Reds (23-28), 3-1 | Riverfront Stadium (0-1) | 22-30 | Lost 2 |
| » W: Joe Price (4-2) L: Joe Niekro (3-5) | Sixth | 13½ out |
| Saturday, June 4 |
| » Defeated Reds (23-29), 13-0 | Riverfront Stadium (1-1) | 23-30 | |
| » W: Mike Scott (1-3) L: Bruce Berenyi (3-6) | Sixth | 13½ out |
| Sunday, June 5 |
| » Defeated Reds (23-30), 6-3 | Riverfront Stadium (2-1) | 24-30 | Won 2 |
| » W: Vern Ruhle (1-1) L: Bill Scherrer (1-3) S: Bill Dawley (4) | Fifth | 12½ out |
| Tuesday, June 7 |
| » Defeated Giants (28-25), 4-2 | Astrodome (13-17) | 25-30 | Won 3 |
| » W: Frank LaCorte (4-2) L: Atlee Hammaker (6-3) S: Frank DiPino (4) | Fifth | 11½ out |
| Wednesday, June 8 |
| » Defeated Giants (28-26), 1-0 | Astrodome (14-17) | 26-30 | Won 4 |
| » W: Bill Dawley (4-1) L: Gary Lavelle (3-1) | Fifth | 11½ out |
| Thursday, June 9 |
| » Defeated Giants (28-27), 3-0 | Astrodome (15-17) | 27-30 | Won 5 |
| » W: Bob Knepper (2-8) L: Mike Krukow (3-4) | Fifth | 11½ out |
| Friday, June 10 |
| » Defeated Padres (26-29), 2-1 | Astrodome (16-17) | 28-30 | Won 6 |
| » W: Mike LaCoss (4-4) L: Ed Whitson (0-4) S: Bill Dawley (5) | Fourth | 10½ out |
| Saturday, June 11 |
| » Lost to Padres (27-29), 8-4 | Astrodome (16-18) | 28-31 | |
| » W: John Montefusco (5-1) L: Vern Ruhle (1-2) | Fifth | 11½ out |
| Sunday, June 12 |
| » Defeated Padres (27-30), 2-0 | Astrodome (17-18) | 29-31 | |
| » W: Nolan Ryan (4-1) L: Eric Show (7-3) | Fourth | 10½ out |
| Monday, June 13 |
| » Defeated Padres (27-31), 2-0 | Astrodome (18-18) | 30-31 | Won 2 |
| » W: Joe Niekro (4-5) L: Dave Dravecky (9-4) S: Frank DiPino (5) | Fourth | 10½ out |
| Tuesday, June 14 |
| » Defeated Giants (30-30), 3-2 | Candlestick Park (1-0) | 31-31 | Won 3 |
| » W: Dave Smith (1-1) L: Greg Minton (1-3) | Fourth | 10½ out |
| Wednesday, June 15 |
| » Lost to Giants (31-30), 7-1 | Candlestick Park (1-1) | 31-32 | |
| » W: Fred Breining (6-4) L: Mike LaCoss (4-5) | Fourth | 10½ out |
| Thursday, June 16 |
| » Defeated Giants (31-31), 7-2 | Candlestick Park (2-1) | 32-32 | |
| » W: Mike Scott (2-3) L: Bill Laskey (7-7) S: Frank DiPino (6) | Fourth | 10½ out |
| Friday, June 17 |
| » Defeated Padres (29-33), 4-1 | San Diego/Jack Murphy Stadium (1-0) | 33-32 | Won 2 |
| » W: Nolan Ryan (5-1) L: Eric Show (7-4) S: Bill Dawley (6) | Third | 10½ out |
| Saturday, June 18 |
| » Lost to Padres (30-33), 2-1 | San Diego/Jack Murphy Stadium (1-1) | 33-33 | |
| » W: Dave Dravecky (10-4) L: Frank LaCorte (4-3) | Fourth | 10½ out |
| Sunday, June 19 |
| » Lost to Padres (31-33), 6-4 | San Diego/Jack Murphy Stadium (1-2) | 33-34 | Lost 2 |
| » W: Elias Sosa (1-1) L: Bob Knepper (2-9) S: Sid Monge (3) | Fourth | 11½ out |
| Monday, June 20 |
| » Lost to Braves (39-27), 7-1 | Astrodome (18-19) | 33-35 | Lost 3 |
| » W: Pete Falcone (5-1) L: Vern Ruhle (1-3) | Fifth | 11½ out |
| Tuesday, June 21 |
| » Defeated Braves (39-28), 5-0 | Astrodome (19-19) | 34-35 | |
| » W: Mike Scott (3-3) L: Phil Niekro (2-6) | Fifth | 10½ out |
| Wednesday, June 22 |
| » Defeated Braves (39-29), 4-3 | Astrodome (20-19) | 35-35 | Won 2 |
| » W: Bill Dawley (5-1) L: Gene Garber (2-3) | Fifth | 9½ out |
| Friday, June 24 |
| » Lost to Dodgers (44-25), 7-2 | Dodger Stadium (0-4) | 35-36 | |
| » W: Burt Hooton (7-2) L: Joe Niekro (4-6) | Fifth | 10 out |
| Saturday, June 25 |
| » Lost to Dodgers (45-25), 2-1 | Dodger Stadium (0-5) | 35-37 | Lost 2 |
| » W: Tom Niedenfuer (4-0) L: Bill Dawley (5-2) | Fourth | 11 out |
| Sunday, June 26 |
| » Defeated Dodgers (45-26), 9-7 | Dodger Stadium (1-5) | 36-37 | |
| » W: Mike Scott (4-3) L: Alejandro Pena (6-3) S: Dave Smith (2) | Fifth | 10 out |
| Tuesday, June 28 |
| » Defeated Braves (44-30), 4-3 | Atlanta-Fulton County Stadium (2-3) | 37-37 | Won 2 |
| » W: Nolan Ryan (6-1) L: Terry Forster (1-2) S: Bill Dawley (7) | Fourth | 10 out |
| Wednesday, June 29 |
| » Lost to Braves (45-30), 11-1 | Atlanta-Fulton County Stadium (2-4) | 37-38 | |
| » W: Ken Dayley (2-0) L: Joe Niekro (4-7) | Fifth | 10 out |
| Thursday, June 30 |
| » Lost to Braves (46-30), 6-4 | Atlanta-Fulton County Stadium (2-5) | 37-39 | Lost 2 |
| » W: Steve Bedrosian (5-2) L: Frank DiPino (3-3) | Fourth | 10 out |
| Friday, July 1 |
| » Lost to Dodgers (47-28), 5-2 | Astrodome (20-20) | 37-40 | Lost 3 |
| » W: Alejandro Pena (7-3) L: Frank LaCorte (4-4) S: Steve Howe (8) | Fifth | 11 out |
| Saturday, July 2 |
| » Defeated Dodgers (47-29), 3-1 | Astrodome (21-20) | 38-40 | |
| » W: Nolan Ryan (7-1) L: Joe Beckwith (0-2) | Fourth | 10 out |
| Sunday, July 3 |
| » Defeated Dodgers (47-30), 8-1 | Astrodome (22-20) | 39-40 | Won 2 |
| » W: Joe Niekro (5-7) L: Bob Welch (6-8) | Fifth | 9 out |
| Monday, July 4 |
| » Defeated Dodgers (47-31), 5-4 | Astrodome (23-20) | 40-40 | Won 3 |
| » W: Dave Smith (2-1) L: Steve Howe (2-3) S: Frank DiPino (7) | Fourth | 9 out |
| Friday, July 8 |
| » Defeated Mets (30-51), 6-3 | Shea Stadium (4-0) | 41-40 | Won 4 |
| » W: Nolan Ryan (8-1) L: Mike Torrez (5-9) | Fourth | 9 out |
| Saturday, July 9 |
| » Defeated Mets (30-52), 7-3 | Shea Stadium (5-0) | 42-40 | Won 5 |
| » W: Joe Niekro (6-7) L: Tom Seaver (5-9) S: Frank DiPino (8) | Fourth | 9 out |
| Sunday, July 10 |
| » Lost to Mets (31-52), 7-5 | Shea Stadium (5-1) | 42-41 | |
| » W: Doug Sisk (3-2) L: Bill Dawley (5-3) | Fourth | 9 out |
| Tuesday, July 12 |
| » Defeated Expos (42-40), 7-5 | Astrodome (24-20) | 43-41 | |
| » W: Vern Ruhle (2-3) L: Randy Lerch (1-3) S: Dave Smith (3) | Fourth | 8 out |
| Wednesday, July 13 |
| » Defeated Expos (42-41), 9-4 | Astrodome (25-20) | 44-41 | Won 2 |
| » W: Nolan Ryan (9-1) L: Charlie Lea (6-6) | Fourth | 8 out |
| Thursday, July 14 |
| » Defeated Expos (42-42), 3-0 | Astrodome (26-20) | 45-41 | Won 3 |
| » W: Joe Niekro (7-7) L: Steve Rogers (12-4) | Third | 8 out |
| Friday, July 15 |
| » Defeated Mets (32-55), 6-0 | Astrodome (27-20) | 46-41 | Won 4 |
| » W: Bob Knepper (3-9) L: Ed Lynch (6-4) | Third | 8 out |
| Saturday, July 16 |
| » Defeated Mets (32-56), 3-1 | Astrodome (28-20) | 47-41 | Won 5 |
| » W: Mike Scott (5-3) L: Mike Torrez (5-11) S: Frank DiPino (9) | Third | 8 out |
| Sunday, July 17 |
| » Lost to Mets (33-56), 3-1 | Astrodome (28-21) | 47-42 | |
| » W: Walt Terrell (2-4) L: Nolan Ryan (9-2) S: Jesse Orosco (9) | Third | 8 out |
| Monday, July 18 |
| » Defeated Phillies (43-43), 8-2 | Veteran's Stadium (2-2) | 48-42 | |
| » W: Joe Niekro (8-7) L: Steve Carlton (9-11) | Third | 8 out |
| Tuesday, July 19 |
| » Defeated Phillies (43-44), 7-3 | Veteran's Stadium (3-2) | 49-42 | Won 2 |
| » W: Bob Knepper (4-9) L: Marty Bystrom (3-5) S: Frank DiPino (10) | Third | 8 out |
| Wednesday, July 20 |
| » Lost to Phillies (44-44), 10-3 | Veteran's Stadium (3-3) | 49-43 | |
| » W: Charles Hudson (3-3) L: Mike Scott (5-4) | Third | 8 out |
| Thursday, July 21 |
| » Lost to Expos (45-45), 9-4 | Stade Olympique (2-1) | 49-44 | Lost 2 |
| » W: Bill Gullickson (8-10) L: Nolan Ryan (9-3) | Third | 8 out |
| Friday, July 22 |
| » Defeated Expos (45-46), 11-8 | Stade Olympique (3-1) | 50-44 | |
| » W: Dave Smith (3-1) L: Woodie Fryman (0-2) S: Bill Dawley (8) | Third | 8 out |
| Saturday, July 23 |
| » Lost to Expos (46-46), 4-1 | Stade Olympique (3-2) | 50-45 | |
| » W: Dan Schatzeder (4-0) L: Bob Knepper (4-10) S: Jeff Reardon (15) | Third | 9 out |
| Sunday, July 24 |
| » Lost to Expos (47-46), 7-3 | Stade Olympique (3-3) | 50-46 | Lost 2 |
| » W: Steve Rogers (13-5) L: Mike LaCoss (4-6) | Third | 10 out |
| Tuesday, July 26 |
| » Lost to Phillies (46-47), 1-0 | Astrodome (28-22) | 50-47 | Lost 3 |
| » W: Charles Hudson (4-3) L: Nolan Ryan (9-4) S: Al Holland (9) | Third | 9½ out |
| Wednesday, July 27 |
| » Lost to Phillies (47-47), 3-1 | Astrodome (28-23) | 50-48 | Lost 4 |
| » W: John Denny (10-5) L: Joe Niekro (8-8) S: Willie Hernandez (6) | Third | 10½ out |
| Thursday, July 28 |
| » Lost to Phillies (48-47), 6-5 | Astrodome (28-24) | 50-49 | Lost 5 |
| » W: Ron Reed (5-1) L: Mike LaCoss (4-7) S: Al Holland (10) | Third | 11 out |
| Friday, July 29 |
| » Defeated Reds (45-57), 4-1 | Astrodome (29-24) | 51-49 | |
| » W: Mike Madden (4-0) L: Joe Price (10-6) S: Dave Smith (4) | Third | 10½ out |
| Saturday, July 30 |
| » Lost to Reds (46-57), 3-2 | Astrodome (29-25) | 51-50 | |
| » W: Mario Soto (12-9) L: Nolan Ryan (9-5) | Third | 11½ out |
| Sunday, July 31 |
| » Defeated Reds (46-58), 9-2 | Astrodome (30-25) | 52-50 | |
| » W: Joe Niekro (9-8) L: Bruce Berenyi (5-11) | Third | 10½ out |
| Monday, August 1 |
| » Lost to Padres (52-52), 7-4 | San Diego/Jack Murphy Stadium (1-3) | 52-51 | |
| » W: Luis DeLeon (2-3) L: Bill Dawley (5-4) | Third | 11½ out |
| Tuesday, August 2 |
| » Defeated Padres (52-53), 4-2 | San Diego/Jack Murphy Stadium (2-3) | 53-51 | |
| » W: Vern Ruhle (3-3) L: Sid Monge (4-1) | Third | 10½ out |
| Wednesday, August 3 |
| » Defeated Padres (52-54), 1-0 | San Diego/Jack Murphy Stadium (3-3) | 54-51 | Won 2 |
| » W: Nolan Ryan (10-5) L: Tim Lollar (4-10) | Third | 10½ out |
| Thursday, August 4 |
| » Lost to Padres (53-54), 4-2 | San Diego/Jack Murphy Stadium (3-4) | 54-52 | |
| » W: Dave Dravecky (13-8) L: Joe Niekro (9-9) S: Gary Lucas (11) | Third | 11½ out |
| Friday, August 5 |
| » Lost to Giants (53-56), 7-1 | Candlestick Park (2-2) | 54-53 | Lost 2 |
| » W: Bill Laskey (12-8) L: Bob Knepper (4-11) | Third | 11½ out |
| Saturday, August 6 |
| » Defeated Giants (53-57), 4-2 | Candlestick Park (3-2) | 55-53 | |
| » W: Mike Madden (5-0) L: Renie Martin (1-2) S: Bill Dawley (9) | Third | 10½ out |
| Sunday, August 7 |
| » Defeated Giants (53-58), 2-1 | Candlestick Park (4-2) | 56-53 | Won 2 |
| » W: Nolan Ryan (11-5) L: Greg Minton (5-8) | Third | 10½ out |
| Tuesday, August 9 |
| » Lost to Padres (56-56), 3-2 | Astrodome (30-26) | 56-54 | |
| » W: Tim Lollar (5-10) L: Joe Niekro (9-10) S: Sid Monge (6) | Third | 11½ out |
| Wednesday, August 10 |
| » Defeated Padres (56-57), 4-3 | Astrodome (31-26) | 57-54 | |
| » W: Vern Ruhle (4-3) L: Luis DeLeon (2-4) | Third | 10½ out |
| Thursday, August 11 |
| » Defeated Padres (56-58), 5-1 | Astrodome (32-26) | 58-54 | Won 2 |
| » W: Mike Scott (6-4) L: Mark Thurmond (5-2) S: Dave Smith (5) | Third | 10½ out |
| Friday, August 12 |
| » Defeated Giants (54-61), 5-2 | Astrodome (33-26) | 59-54 | Won 3 |
| » W: Nolan Ryan (12-5) L: Renie Martin (1-3) S: Frank DiPino (11) | Third | 9½ out |
| Saturday, August 13 |
| » Defeated Giants (54-62), 4-1 | Astrodome (34-26) | 60-54 | Won 4 |
| » W: Joe Niekro (10-10) L: Mike Krukow (7-7) S: Bill Dawley (10) | Third | 9½ out |
| Sunday, August 14 |
| » Lost to Giants (55-62), 5-2 | Astrodome (34-27) | 60-55 | |
| » W: Mark Davis (2-3) L: Mike Madden (5-1) S: Gary Lavelle (14) | Third | 9½ out |
| Monday, August 15 |
| » Defeated Reds (54-65), 9-1 | Riverfront Stadium (3-1) | 61-55 | |
| » W: Bob Knepper (5-11) L: Bruce Berenyi (6-12) | Third | 8½ out |
| Tuesday, August 16 |
| » Defeated Reds (54-66), 8-5 | Riverfront Stadium (4-1) | 62-55 | Won 2 |
| » W: Mike Scott (7-4) L: Charlie Puleo (4-9) S: Bill Dawley (11) | Third | 7½ out |
| Wednesday, August 17 |
| » Defeated Reds (54-67), 7-6 | Riverfront Stadium (5-1) | 63-55 | Won 3 |
| » W: Vern Ruhle (5-3) L: Frank Pastore (6-11) | Third | 7 out |
| Thursday, August 18 |
| » Lost to Cardinals (57-61), 5-4 | Busch Stadium II (0-3) | 63-56 | |
| » W: Dave Rucker (5-3) L: Bill Dawley (5-5) | Third | 7 out |
| Friday, August 19 |
| » Lost to Cardinals (58-61), 2-0 | Busch Stadium II (0-4) | 63-57 | Lost 2 |
| » W: Dave LaPoint (11-7) L: Mike Madden (5-2) S: Bruce Sutter (13) | Third | 8 out |
| Saturday, August 20 |
| » Lost to Cardinals (59-61), 3-0 | Busch Stadium II (0-5) | 63-58 | Lost 3 |
| » W: John Stuper (8-8) L: Bob Knepper (5-12) | Third | 9 out |
| Sunday, August 21 |
| » Lost to Cardinals (60-61), 5-2 | Busch Stadium II (0-6) | 63-59 | Lost 4 |
| » W: Danny Cox (1-1) L: Nolan Ryan (12-6) S: Bruce Sutter (14) | Third | 10 out |
| Tuesday, August 23 |
| » Defeated Pirates (63-59), 6-5 | Three Rivers Stadium (2-1) | 64-59 | |
| » W: Vern Ruhle (6-3) L: Kent Tekulve (6-4) S: Frank DiPino (12) | Third | 8½ out |
| » Defeated Pirates (63-60), 2-1 | Three Rivers Stadium (3-1) | 65-59 | Won 2 |
| » W: Joe Niekro (11-10) L: Lee Tunnell (6-5) S: Bill Dawley (12) | Third | 8½ out |
| Wednesday, August 24 |
| » Defeated Pirates (63-61), 10-4 | Three Rivers Stadium (4-1) | 66-59 | Won 3 |
| » W: Mike Madden (6-2) L: Rick Rhoden (9-11) S: Mike LaCoss (1) | Third | 8½ out |
| Thursday, August 25 |
| » Lost to Pirates (64-61), 5-3 | Three Rivers Stadium (4-2) | 66-60 | |
| » W: Jose DeLeon (5-2) L: Bob Knepper (5-13) S: Rod Scurry (7) | Third | 8½ out |
| Friday, August 26 |
| » Defeated Cubs (56-71), 1-0 | Astrodome (35-27) | 67-60 | |
| » W: Vern Ruhle (7-3) L: Steve Trout (9-12) S: Bill Dawley (13) | Third | 7½ out |
| Saturday, August 27 |
| » Lost to Cubs (57-71), 9-5 | Astrodome (35-28) | 67-61 | |
| » W: Dick Ruthven (10-10) L: Joe Niekro (11-11) S: Bill Campbell (8) | Third | 7½ out |
| Sunday, August 28 |
| » Defeated Cubs (57-72), 4-2 | Astrodome (36-28) | 68-61 | |
| » W: Mike Scott (8-4) L: Dickie Noles (5-8) S: Frank DiPino (13) | Third | 7½ out |
| Monday, August 29 |
| » Lost to Cardinals (64-64), 6-1 | Astrodome (36-29) | 68-62 | |
| » W: John Stuper (9-8) L: Mike Madden (6-3) | Third | 8½ out |
| Tuesday, August 30 |
| » Defeated Cardinals (64-65), 3-1 | Astrodome (37-29) | 69-62 | |
| » W: Vern Ruhle (8-3) L: Danny Cox (1-3) S: Bill Dawley (14) | Third | 8 out |
| Wednesday, August 31 |
| » Defeated Pirates (68-63), 4-1 | Astrodome (38-29) | 70-62 | Won 2 |
| » W: Joe Niekro (12-11) L: Rod Scurry (4-8) | Third | 7 out |
| Thursday, September 1 |
| » Defeated Pirates (68-64), 3-0 | Astrodome (39-29) | 71-62 | Won 3 |
| » W: Nolan Ryan (13-6) L: Cecilio Guante (2-2) S: Frank DiPino (14) | Third | 6 out |
| » Major-league debuts: Joe Orsulak (Pirates) |
| Friday, September 2 |
| » Defeated Cubs (60-74), 6-5 | Wrigley Field (3-1) | 72-62 | Won 4 |
| » W: Bill Dawley (6-5) L: Bill Campbell (4-8) S: Frank DiPino (15) | Third | 6 out |
| » Major-league debuts: Dan Rohn (Cubs) |
| Saturday, September 3 |
| » Lost to Cubs (61-74), 9-3 | Wrigley Field (3-2) | 72-63 | |
| » W: Fergie Jenkins (5-9) L: Mike Madden (6-4) S: Rich Bordi (1) | Third | 7 out |
| » Major-league debuts: Jeff Heathcock (Astros) |
| Sunday, September 4 |
| » Lost to Cubs (62-74), 9-7 | Wrigley Field (3-3) | 72-64 | Lost 2 |
| » W: Warren Brusstar (3-1) L: Bill Dawley (6-6) S: Lee Smith (24) | Third | 7 out |
| Monday, September 5 |
| » Lost to Braves (78-60), 7-5 | Atlanta-Fulton County Stadium (2-6) | 72-65 | Lost 3 |
| » W: Len Barker (9-14) L: Joe Niekro (12-12) S: Donnie Moore (6) | Third | 7 out |
| Wednesday, September 7 |
| » Lost to Padres (70-71), 8-7 | San Diego/Jack Murphy Stadium (3-5) | 72-66 | Lost 4 |
| » W: Sid Monge (7-2) L: Frank DiPino (3-4) | Third | 7½ out |
| Thursday, September 8 |
| » Defeated Padres (70-72), 3-2 | San Diego/Jack Murphy Stadium (4-5) | 73-66 | |
| » W: Mike Madden (7-4) L: Luis DeLeon (4-6) S: Vern Ruhle (2) | Third | 7½ out |
| Friday, September 9 |
| » Defeated Giants (67-75), 7-4 | Candlestick Park (5-2) | 74-66 | Won 2 |
| » W: Joe Niekro (13-12) L: Mark Davis (3-4) S: Frank DiPino (16) | Third | 7½ out |
| Saturday, September 10 |
| » Defeated Giants (67-76), 5-3 | Candlestick Park (6-2) | 75-66 | Won 3 |
| » W: Jeff Heathcock (1-0) L: Fred Breining (9-12) | Third | 6½ out |
| Sunday, September 11 |
| » Lost to Giants (68-76), 3-2 | Candlestick Park (6-3) | 75-67 | |
| » W: Greg Minton (7-10) L: Nolan Ryan (13-7) | Third | 7½ out |
| Tuesday, September 13 |
| » Lost to Dodgers (84-60), 5-1 | Astrodome (39-30) | 75-68 | Lost 2 |
| » W: Jerry Reuss (11-10) L: Mike Scott (8-5) | Third | 8½ out |
| Wednesday, September 14 |
| » Defeated Dodgers (84-61), 4-2 | Astrodome (40-30) | 76-68 | |
| » W: Joe Niekro (14-12) L: Bob Welch (14-12) | Third | 7½ out |
| Thursday, September 15 |
| » Lost to Dodgers (85-61), 6-0 | Astrodome (40-31) | 76-69 | |
| » W: Alejandro Pena (12-6) L: Nolan Ryan (13-8) | Third | 8½ out |
| Friday, September 16 |
| » Lost to Reds (68-79), 8-3 | Riverfront Stadium (5-2) | 76-70 | Lost 2 |
| » W: Bruce Berenyi (8-14) L: Jeff Heathcock (1-1) | Third | 8½ out |
| Saturday, September 17 |
| » Defeated Reds (68-80), 4-3 | Riverfront Stadium (6-2) | 77-70 | |
| » W: Mike Madden (8-4) L: Jeff Russell (3-3) S: Frank DiPino (17) | Third | 7½ out |
| Sunday, September 18 |
| » Defeated Reds (68-81), 4-1 | Riverfront Stadium (7-2) | 78-70 | Won 2 |
| » W: Mike Scott (9-5) L: Mario Soto (16-13) S: Frank DiPino (18) | Third | 6½ out |
| Monday, September 19 |
| » Lost to Dodgers (86-64), 9-2 | Dodger Stadium (1-6) | 78-71 | |
| » W: Bob Welch (15-12) L: Joe Niekro (14-13) | Third | 7½ out |
| Tuesday, September 20 |
| » Defeated Dodgers (86-65), 15-2 | Dodger Stadium (2-6) | 79-71 | |
| » W: Nolan Ryan (14-8) L: Alejandro Pena (12-7) S: Jeff Heathcock (1) | Third | 6½ out |
| » Major-league debuts: Sid Fernandez (Dodgers) |
| Wednesday, September 21 |
| » Lost to Dodgers (87-65), 2-1 | Dodger Stadium (2-7) | 79-72 | |
| » W: Fernando Valenzuela (14-10) L: Vern Ruhle (8-4) | Third | 7½ out |
| Friday, September 23 |
| » Lost to Giants (74-79), 3-2 | Astrodome (40-32) | 79-73 | Lost 2 |
| » W: Fred Breining (11-12) L: Joe Niekro (14-14) S: Greg Minton (20) | Third | 8½ out |
| Saturday, September 24 |
| » Defeated Giants (74-80), 6-5 | Astrodome (41-32) | 80-73 | |
| » W: Mike Scott (10-5) L: Mike Krukow (11-10) S: Frank DiPino (19) | Third | 7½ out |
| Sunday, September 25 |
| » Lost to Giants (75-80), 3-0 | Astrodome (41-33) | 80-74 | |
| » W: Scott Garrelts (2-1) L: Nolan Ryan (14-9) | Third | 7½ out |
| Monday, September 26 |
| » Defeated Padres (77-79), 5-3 | Astrodome (42-33) | 81-74 | |
| » W: Mike Madden (9-4) L: Eric Show (14-12) S: Vern Ruhle (3) | Third | 7½ out |
| Tuesday, September 27 |
| » Defeated Padres (77-80), 8-5 | Astrodome (43-33) | 82-74 | |