| Wednesday, January 26 |
| Former Cub Del Rice dies in Buena Park, CA at the age of 61. |
| Sunday, April 3 |
| Former Cub Mickey Livingston dies in Newberry, SC at the age of 69. |
| Wednesday, April 6 |
| » Lost to Expos (1-0), 3-0 | Wrigley Field (0-1) | 0-1 | |
| » W: Steve Rogers (1-0) L: Fergie Jenkins (0-1) | Second | 1 out |
| Thursday, April 7 |
| » Lost to Expos (2-0), 7-3 | Wrigley Field (0-2) | 0-2 | Lost 2 |
| » W: Bill Gullickson (1-0) L: Dickie Noles (0-1) | Third | 2 out |
| » Major-league debuts: Craig Lefferts (Cubs) |
| Friday, April 8 |
| » Lost to Reds (2-1), 7-3 | Riverfront Stadium (0-1) | 0-3 | Lost 3 |
| » W: Mario Soto (2-0) L: Steve Trout (0-1) | Fourth | 3 out |
| Saturday, April 9 |
| » Lost to Reds (3-1), 8-4 | Riverfront Stadium (0-2) | 0-4 | Lost 4 |
| » W: Frank Pastore (1-0) L: Chuck Rainey (0-1) | Fifth | 4 out |
| » Major-league debuts: Tom Foley (Reds) Steve Lake (Cubs) |
| Sunday, April 10 |
| » Lost to Reds (4-1), 7-2 | Riverfront Stadium (0-3) | 0-5 | Lost 5 |
| » W: Bruce Berenyi (1-1) L: Fergie Jenkins (0-2) | Sixth | 5 out |
| Monday, April 11 |
| » Lost to Reds (5-1), 5-1 | Riverfront Stadium (0-4) | 0-6 | Lost 6 |
| » W: Joe Price (1-0) L: Dickie Noles (0-2) | Sixth | 5½ out |
| » Major-league debuts: Dann Bilardello (Reds) |
| Tuesday, April 12 |
| » Defeated Expos (4-2), 5-0 | Stade Olympique (1-0) | 1-6 | |
| » W: Steve Trout (1-1) L: Bill Gullickson (1-1) | Sixth | 4½ out |
| Thursday, April 14 |
| » Lost to Expos (5-2), 4-3 | Stade Olympique (1-1) | 1-7 | |
| » W: Scott Sanderson (2-0) L: Chuck Rainey (0-2) S: Jeff Reardon (1) | Fifth | 4½ out |
| Saturday, April 16 |
| » Defeated Pirates (5-3), 6-5 | Three Rivers Stadium (1-0) | 2-7 | |
| » W: Willie Hernandez (1-0) L: Larry McWilliams (1-1) S: Lee Smith (1) | Fifth | 5 out |
| Sunday, April 17 |
| » Lost to Pirates (6-3), 7-0 | Three Rivers Stadium (1-1) | 2-8 | |
| » W: John Candelaria (2-0) L: Steve Trout (1-2) S: Rick Rhoden (1) | Sixth | 5½ out |
| Former Cub Dutch Leonard dies in Springfield, IL at the age of 75. |
| Monday, April 18 |
| » Lost to Phillies (6-4), 8-2 | Veteran's Stadium (0-1) | 2-9 | Lost 2 |
| » W: John Denny (1-1) L: Paul Moskau (0-1) | Fifth | 6 out |
| Wednesday, April 20 |
| » Lost to Phillies (7-4), 2-0 | Veteran's Stadium (0-2) | 2-10 | Lost 3 |
| » W: Steve Carlton (3-1) L: Chuck Rainey (0-3) | Sixth | 6½ out |
| Friday, April 22 |
| » Defeated Giants (4-11), 7-2 | Wrigley Field (1-2) | 3-10 | |
| » W: Fergie Jenkins (1-2) L: Bill Laskey (0-4) S: Willie Hernandez (1) | Fifth | 5½ out |
| Saturday, April 23 |
| » Lost to Giants (5-11), 5-0 | Wrigley Field (1-3) | 3-11 | |
| » W: Atlee Hammaker (2-1) L: Steve Trout (1-3) | Sixth | 6 out |
| Sunday, April 24 |
| » Defeated Giants (5-12), 5-1 | Wrigley Field (2-3) | 4-11 | |
| » W: Paul Moskau (1-1) L: Andy McGaffigan (0-2) S: Lee Smith (2) | Sixth | 6 out |
| Tuesday, April 26 |
| » Lost to Padres (8-10), 10-8 | Wrigley Field (2-4) | 4-12 | |
| » W: John Montefusco (2-1) L: Craig Lefferts (0-1) S: Luis DeLeon (2) | Sixth | 6 out |
| Wednesday, April 27 |
| » Defeated Padres (8-11), 5-4 | Wrigley Field (3-4) | 5-12 | |
| » W: Bill Campbell (1-0) L: Gary Lucas (0-1) | Sixth | 5½ out |
| Thursday, April 28 |
| » Lost to Padres (9-11), 3-1 | Wrigley Field (3-5) | 5-13 | |
| » W: Eric Show (3-1) L: Steve Trout (1-4) S: Luis DeLeon (3) | Sixth | 6 out |
| Friday, April 29 |
| » Lost to Dodgers (14-5), 4-3 | Wrigley Field (3-6) | 5-14 | Lost 2 |
| » W: Alejandro Pena (3-1) L: Bill Campbell (1-1) | Sixth | 6½ out |
| Saturday, April 30 |
| » Defeated Dodgers (14-6), 7-2 | Wrigley Field (4-6) | 6-14 | |
| » W: Chuck Rainey (1-3) L: Fernando Valenzuela (3-2) | Sixth | 6 out |
| Sunday, May 1 |
| » Lost to Dodgers (15-6), 3-2 | Wrigley Field (4-7) | 6-15 | |
| » W: Dave Stewart (1-0) L: Fergie Jenkins (1-3) | Sixth | 7 out |
| Tuesday, May 3 |
| » Lost to Giants (8-15), 5-4 | Candlestick Park (0-1) | 6-16 | Lost 2 |
| » W: Bill Laskey (2-4) L: Steve Trout (1-5) | Sixth | 7½ out |
| Wednesday, May 4 |
| » Lost to Giants (9-15), 7-4 | Candlestick Park (0-2) | 6-17 | Lost 3 |
| » W: Atlee Hammaker (3-1) L: Paul Moskau (1-2) | Sixth | 8½ out |
| Friday, May 6 |
| » Defeated Padres (12-14), 3-2 | San Diego/Jack Murphy Stadium (1-0) | 7-17 | |
| » W: Chuck Rainey (2-3) L: Tim Lollar (1-2) S: Lee Smith (3) | Sixth | 8½ out |
| Saturday, May 7 |
| » Defeated Padres (12-15), 6-4 | San Diego/Jack Murphy Stadium (2-0) | 8-17 | Won 2 |
| » W: Bill Campbell (2-1) L: Gary Lucas (0-3) | Fifth | 7½ out |
| Sunday, May 8 |
| » Lost to Padres (13-15), 5-3 | San Diego/Jack Murphy Stadium (2-1) | 8-18 | |
| » W: Dave Dravecky (5-1) L: Warren Brusstar (0-1) | Sixth | 8 out |
| Monday, May 9 |
| » Lost to Dodgers (21-7), 4-3 | Dodger Stadium (0-1) | 8-19 | Lost 2 |
| » W: Dave Stewart (3-0) L: Lee Smith (0-1) | Sixth | 8½ out |
| Tuesday, May 10 |
| » Defeated Dodgers (21-8), 3-2 | Dodger Stadium (1-1) | 9-19 | |
| » W: Mike Proly (1-0) L: Bob Welch (1-3) S: Lee Smith (4) | Fifth | 8½ out |
| Thursday, May 12 |
| » Defeated Phillies (16-11), 6-3 | Wrigley Field (5-7) | 10-19 | Won 2 |
| » W: Chuck Rainey (3-3) L: Dick Ruthven (1-2) S: Bill Campbell (1) | Fifth | 7 out |
| Friday, May 13 |
| » Defeated Phillies (16-12), 10-2 | Wrigley Field (6-7) | 11-19 | Won 3 |
| » W: Steve Trout (2-5) L: Larry Christenson (1-3) | Fifth | 6 out |
| Sunday, May 15 |
| » Lost to Phillies (17-12), 5-3 | Wrigley Field (6-8) | 11-20 | |
| » W: Steve Carlton (6-2) L: Lee Smith (0-2) S: Ron Reed (3) | Fourth | 7 out |
| Monday, May 16 |
| Former Cub Mel Wright dies in Houston, TX at the age of 56. |
| Tuesday, May 17 |
| » Defeated Braves (22-12), 4-3 | Wrigley Field (7-8) | 12-20 | |
| » W: Chuck Rainey (4-3) L: Pascual Perez (5-1) S: Mike Proly (1) | Fourth | 7 out |
| Wednesday, May 18 |
| » Defeated Braves (22-13), 5-3 | Wrigley Field (8-8) | 13-20 | Won 2 |
| » W: Steve Trout (3-5) L: Rick Behenna (3-2) S: Bill Campbell (2) | Fifth | 7 out |
| Friday, May 20 |
| » Lost to Reds (17-21), 9-5 | Wrigley Field (8-9) | 13-21 | |
| » W: Bill Scherrer (1-1) L: Mike Proly (1-1) | Sixth | 7 out |
| Saturday, May 21 |
| » Defeated Reds (17-22), 8-4 | Wrigley Field (9-9) | 14-21 | |
| » W: Paul Moskau (2-2) L: Charlie Puleo (0-1) | Fifth | 6 out |
| Sunday, May 22 |
| » Lost to Reds (18-22), 4-3 | Wrigley Field (9-10) | 14-22 | |
| » W: Mario Soto (6-2) L: Chuck Rainey (4-4) | Fifth | 6 out |
| Monday, May 23 |
| » Lost to Astros (18-24), 3-2 | Astrodome (0-1) | 14-23 | Lost 2 |
| » W: Joe Niekro (2-4) L: Steve Trout (3-6) S: Frank DiPino (2) | Sixth | 6 out |
| Tuesday, May 24 |
| » Defeated Astros (18-25), 5-4 | Astrodome (1-1) | 15-23 | |
| » W: Dick Ruthven (2-3) L: Mike Scott (0-2) S: Bill Campbell (3) | Fifth | 6 out |
| Wednesday, May 25 |
| » Lost to Astros (19-25), 1-0 | Astrodome (1-2) | 15-24 | |
| » W: Mike Madden (3-0) L: Craig Lefferts (0-2) S: Bill Dawley (3) | Fifth | 7 out |
| Thursday, May 26 |
| » Defeated Braves (27-15), 5-1 | Atlanta-Fulton County Stadium (1-0) | 16-24 | |
| » W: Paul Moskau (3-2) L: Phil Niekro (1-4) | Fifth | 7 out |
| Friday, May 27 |
| » Defeated Braves (27-16), 8-6 | Atlanta-Fulton County Stadium (2-0) | 17-24 | Won 2 |
| » W: Warren Brusstar (1-1) L: Rick Behenna (3-3) S: Lee Smith (5) | Fifth | 7 out |
| Saturday, May 28 |
| » Lost to Braves (28-16), 6-4 | Atlanta-Fulton County Stadium (2-1) | 17-25 | |
| » W: Donnie Moore (1-0) L: Mike Proly (1-2) S: Steve Bedrosian (5) | Fifth | 7 out |
| Sunday, May 29 |
| » Lost to Braves (29-16), 6-2 | Atlanta-Fulton County Stadium (2-2) | 17-26 | Lost 2 |
| » W: Rick Camp (4-4) L: Dick Ruthven (2-4) S: Terry Forster (6) | Fifth | 8 out |
| Monday, May 30 |
| » Lost to Astros (21-28), 9-7 | Wrigley Field (9-11) | 17-27 | Lost 3 |
| » W: Bill Dawley (3-1) L: Bill Campbell (2-2) S: Frank DiPino (3) | Fifth | 9 out |
| Tuesday, May 31 |
| » Lost to Astros (22-28), 12-10 | Wrigley Field (9-12) | 17-28 | Lost 4 |
| » W: Frank LaCorte (3-2) L: Craig Lefferts (0-3) S: Dave Smith (1) | Fifth | 9 out |
| Wednesday, June 1 |
| » Defeated Astros (22-29), 3-2 | Wrigley Field (10-12) | 18-28 | |
| » W: Chuck Rainey (5-4) L: Bob Knepper (1-8) S: Lee Smith (6) | Fifth | 9 out |
| Thursday, June 2 |
| » Defeated Pirates (18-26), 3-2 | Wrigley Field (11-12) | 19-28 | Won 2 |
| » W: Steve Trout (4-6) L: Rick Rhoden (2-5) S: Lee Smith (7) | Fifth | 8 out |
| Friday, June 3 |
| » Defeated Pirates (18-27), 9-3 | Wrigley Field (12-12) | 20-28 | Won 3 |
| » W: Dick Ruthven (3-4) L: Rod Scurry (2-3) | Fourth | 7 out |
| Saturday, June 4 |
| » Defeated Pirates (18-28), 5-2 | Wrigley Field (13-12) | 21-28 | Won 4 |
| » W: Fergie Jenkins (2-3) L: Jim Bibby (2-6) S: Bill Campbell (4) | Fourth | 6 out |
| Sunday, June 5 |
| » Defeated Pirates (18-29), 3-1 | Wrigley Field (14-12) | 22-28 | Won 5 |
| » W: Craig Lefferts (1-3) L: Lee Tunnell (1-3) S: Lee Smith (8) | Fourth | 6 out |
| Tuesday, June 7 |
| » Defeated Mets (18-32), 6-1 | Wrigley Field (15-12) | 23-28 | Won 6 |
| » W: Chuck Rainey (6-4) L: Jesse Orosco (3-2) S: Bill Campbell (5) | Fourth | 6 out |
| Wednesday, June 8 |
| » Defeated Mets (18-33), 2-1 | Wrigley Field (16-12) | 24-28 | Won 7 |
| » W: Lee Smith (1-2) L: Mike Torrez (2-7) | Fourth | 5 out |
| Thursday, June 9 |
| » Lost to Mets (19-33), 6-4 | Wrigley Field (16-13) | 24-29 | |
| » W: Jesse Orosco (4-2) L: Mike Proly (1-3) | Fourth | 5 out |
| Friday, June 10 |
| » Defeated Cardinals (28-24), 7-0 | Wrigley Field (17-13) | 25-29 | |
| » W: Fergie Jenkins (3-3) L: John Stuper (7-3) | Fourth | 4 out |
| Saturday, June 11 |
| » Lost to Cardinals (29-24), 5-4 | Wrigley Field (17-14) | 25-30 | |
| » W: Bruce Sutter (5-3) L: Lee Smith (1-3) S: Joaquin Andujar (1) | Fourth | 5 out |
| Sunday, June 12 |
| » Defeated Cardinals (29-25), 6-3 | Wrigley Field (18-14) | 26-30 | |
| » W: Chuck Rainey (7-4) L: Bob Forsch (4-5) S: Lee Smith (9) | Fourth | 4 out |
| Monday, June 13 |
| » Defeated Mets (21-35), 7-3 | Shea Stadium (1-0) | 27-30 | Won 2 |
| » W: Steve Trout (5-6) L: Mike Torrez (2-8) S: Craig Lefferts (1) | Fourth | 3 out |
| Tuesday, June 14 |
| » Lost to Mets (22-35), 4-3 | Shea Stadium (1-1) | 27-31 | |
| » W: Doug Sisk (2-1) L: Lee Smith (1-4) | Fourth | 4 out |
| Former Cub Speed Martin dies in Lemon Grove, CA at the age of 90. |
| Wednesday, June 15 |
| » Defeated Mets (22-36), 7-4 | Shea Stadium (2-1) | 28-31 | |
| » W: Lee Smith (2-4) L: Scott Holman (1-5) | Fourth | 4 out |
| Friday, June 17 |
| » Lost to Cardinals (32-26), 7-2 | Busch Stadium II (0-1) | 28-32 | |
| » W: Bob Forsch (5-5) L: Chuck Rainey (7-5) | Fourth | 5 out |
| » Major-league debuts: Andy Van Slyke (Cardinals) |
| Saturday, June 18 |
| » Defeated Cardinals (32-27), 10-1 | Busch Stadium II (1-1) | 29-32 | |
| » W: Steve Trout (6-6) L: Joaquin Andujar (3-9) | Fourth | 4 out |
| Sunday, June 19 |
| » Defeated Cardinals (32-28), 4-1 | Busch Stadium II (2-1) | 30-32 | Won 2 |
| » W: Dick Ruthven (4-4) L: Dave LaPoint (4-4) | Third | 3 out |
| Monday, June 20 |
| » Lost to Pirates (24-36), 5-4 | Three Rivers Stadium (1-2) | 30-33 | |
| » W: Kent Tekulve (3-1) L: Bill Campbell (2-3) | Fourth | 4½ out |
| » Lost to Pirates (25-36), 6-5 | Three Rivers Stadium (1-3) | 30-34 | Lost 2 |
| » W: Don Robinson (1-0) L: Bill Campbell (2-4) | Fourth | 4½ out |
| Tuesday, June 21 |
| » Lost to Pirates (26-36), 8-4 | Three Rivers Stadium (1-4) | 30-35 | Lost 3 |
| » W: Rick Rhoden (4-7) L: Dickie Noles (0-3) | Third | 5 out |
| Wednesday, June 22 |
| » Lost to Pirates (27-36), 5-2 | Three Rivers Stadium (1-5) | 30-36 | Lost 4 |
| » W: John Candelaria (6-6) L: Chuck Rainey (7-6) S: Cecilio Guante (1) | Fourth | 6 out |
| Thursday, June 23 |
| » Lost to Pirates (28-36), 5-2 | Three Rivers Stadium (1-6) | 30-37 | Lost 5 |
| » W: Larry McWilliams (8-5) L: Steve Trout (6-7) | Fourth | 7 out |
| Friday, June 24 |
| » Lost to Expos (37-29), 4-3 | Stade Olympique (1-2) | 30-38 | Lost 6 |
| » W: Steve Rogers (10-3) L: Dick Ruthven (4-5) S: Jeff Reardon (12) | Fifth | 8 out |
| Saturday, June 25 |
| » Defeated Expos (37-30), 2-1 | Stade Olympique (2-2) | 31-38 | |
| » W: Warren Brusstar (2-1) L: Chris Welsh (0-2) | Fifth | 7 out |
| Sunday, June 26 |
| » Defeated Expos (37-31), 9-5 | Stade Olympique (3-2) | 32-38 | Won 2 |
| » W: Dickie Noles (1-3) L: Randy Lerch (1-1) | Fifth | 6 out |
| Monday, June 27 |
| » Lost to Expos (38-31), 3-1 | Stade Olympique (3-3) | 32-39 | |
| » W: Charlie Lea (6-3) L: Chuck Rainey (7-7) | Fifth | 7 out |
| Tuesday, June 28 |
| » Defeated Pirates (32-37), 8-7 | Wrigley Field (19-14) | 33-39 | |
| » W: Craig Lefferts (2-3) L: Kent Tekulve (3-2) | Fifth | 6½ out |
| Wednesday, June 29 |
| » Defeated Pirates (32-38), 5-0 | Wrigley Field (20-14) | 34-39 | Won 2 |
| » W: Dick Ruthven (5-5) L: Jim Bibby (3-8) | Fourth | 6 out |
| Thursday, June 30 |
| » Defeated Pirates (32-39), 4-3 | Wrigley Field (21-14) | 35-39 | Won 3 |
| » W: Lee Smith (3-4) L: Manny Sarmiento (1-2) | Fourth | 5 out |
| Friday, July 1 |
| » Defeated Expos (39-34), 7-5 | Wrigley Field (22-14) | 36-39 | Won 4 |
| » W: Dickie Noles (2-3) L: Randy Lerch (1-2) S: Lee Smith (10) | Fourth | 4 out |
| Saturday, July 2 |
| » Defeated Expos (39-35), 5-2 | Wrigley Field (23-14) | 37-39 | Won 5 |
| » W: Chuck Rainey (8-7) L: Charlie Lea (6-4) S: Warren Brusstar (1) | Fourth | 3 out |
| Sunday, July 3 |
| » Defeated Expos (39-36), 7-4 | Wrigley Field (24-14) | 38-39 | Won 6 |
| » W: Steve Trout (7-7) L: Bill Gullickson (7-9) S: Bill Campbell (6) | Fourth | 2 out |
| Monday, July 4 |
| » Lost to Expos (40-36), 6-3 | Wrigley Field (24-15) | 38-40 | |
| » W: Steve Rogers (12-3) L: Dick Ruthven (5-6) S: Dan Schatzeder (1) | Fourth | 4 out |
| » Lost to Expos (41-36), 4-2 | Wrigley Field (24-16) | 38-41 | Lost 2 |
| » W: Scott Sanderson (5-6) L: Fergie Jenkins (3-4) S: Jeff Reardon (13) | Fourth | 4 out |
| Friday, July 8 |
| » Lost to Giants (40-40), 4-1 | Candlestick Park (0-3) | 38-42 | Lost 3 |
| » W: Bill Laskey (10-7) L: Dickie Noles (2-4) S: Gary Lavelle (12) | Fourth | 4 out |
| Saturday, July 9 |
| » Defeated Giants (40-41), 4-2 | Candlestick Park (1-3) | 39-42 | |
| » W: Chuck Rainey (9-7) L: Mark Davis (0-3) S: Lee Smith (11) | Fourth | 3 out |
| Sunday, July 10 |
| » Lost to Giants (41-41), 10-8 | Candlestick Park (1-4) | 39-43 | |
| » W: Gary Lavelle (6-2) L: Bill Campbell (2-5) S: Renie Martin (1) | Fourth | 4½ out |
| » Lost to Giants (42-41), 4-2 | Candlestick Park (1-5) | 39-44 | Lost 2 |
| » W: Atlee Hammaker (10-4) L: Dick Ruthven (5-7) | Fourth | 4½ out |
| Monday, July 11 |
| » Lost to Padres (43-40), 6-5 | San Diego/Jack Murphy Stadium (2-2) | 39-45 | Lost 3 |
| » W: John Montefusco (8-1) L: Fergie Jenkins (3-5) S: Sid Monge (4) | Fourth | 4½ out |
| Tuesday, July 12 |
| » Lost to Padres (44-40), 5-3 | San Diego/Jack Murphy Stadium (2-3) | 39-46 | Lost 4 |
| » W: Eric Show (9-5) L: Dickie Noles (2-5) | Fifth | 5½ out |
| Wednesday, July 13 |
| » Lost to Padres (45-40), 5-4 | San Diego/Jack Murphy Stadium (2-4) | 39-47 | Lost 5 |
| » W: Tim Lollar (4-6) L: Chuck Rainey (9-8) S: Gary Lucas (10) | Fifth | 5½ out |
| Thursday, July 14 |
| » Lost to Dodgers (51-34), 8-4 | Dodger Stadium (1-2) | 39-48 | Lost 6 |
| » W: Alejandro Pena (8-4) L: Steve Trout (7-8) S: Tom Niedenfuer (2) | Fifth | 5½ out |
| Friday, July 15 |
| » Defeated Dodgers (51-35), 8-4 | Dodger Stadium (2-2) | 40-48 | |
| » W: Dick Ruthven (6-7) L: Burt Hooton (8-3) S: Lee Smith (12) | Fifth | 4½ out |
| Saturday, July 16 |
| » Lost to Dodgers (52-35), 7-4 | Dodger Stadium (2-3) | 40-49 | |
| » W: Fernando Valenzuela (9-5) L: Fergie Jenkins (3-6) S: Tom Niedenfuer (3) | Fifth | 5½ out |
| Sunday, July 17 |
| » Defeated Dodgers (52-36), 10-0 | Dodger Stadium (3-3) | 41-49 | |
| » W: Dickie Noles (3-5) L: Bob Welch (7-9) | Fifth | 4½ out |
| Tuesday, July 19 |
| » Lost to Giants (45-46), 4-3 | Wrigley Field (24-17) | 41-50 | |
| » W: Greg Minton (3-6) L: Bill Campbell (2-6) | Fifth | 5½ out |
| Wednesday, July 20 |
| » Lost to Giants (46-46), 4-3 | Wrigley Field (24-18) | 41-51 | Lost 2 |
| » W: Greg Minton (4-6) L: Lee Smith (3-5) | Fifth | 5½ out |
| Thursday, July 21 |
| » Defeated Giants (46-47), 3-2 | Wrigley Field (25-18) | 42-51 | |
| » W: Dick Ruthven (7-7) L: Atlee Hammaker (10-5) S: Lee Smith (13) | Fifth | 5½ out |
| Friday, July 22 |
| » Defeated Padres (47-46), 7-3 | Wrigley Field (26-18) | 43-51 | Won 2 |
| » W: Craig Lefferts (3-3) L: Gary Lucas (4-6) | Fifth | 4½ out |
| Saturday, July 23 |
| » Lost to Padres (48-46), 4-2 | Wrigley Field (26-19) | 43-52 | |
| » W: Eric Show (10-6) L: Dickie Noles (3-6) S: John Montefusco (3) | Fifth | 5½ out |
| Sunday, July 24 |
| » Defeated Padres (48-47), 5-2 | Wrigley Field (27-19) | 44-52 | |
| » W: Chuck Rainey (10-8) L: Tim Lollar (4-8) S: Lee Smith (14) | Fifth | 5 out |
| Monday, July 25 |
| » Defeated Dodgers (55-41), 9-3 | Wrigley Field (28-19) | 45-52 | Won 2 |
| » W: Steve Trout (8-8) L: Burt Hooton (8-5) | Fifth | 5 out |
| Tuesday, July 26 |
| » Lost to Dodgers (56-41), 5-2 | Wrigley Field (28-20) | 45-53 | |
| » W: Fernando Valenzuela (10-5) L: Dick Ruthven (7-8) | Fifth | 5½ out |
| Wednesday, July 27 |
| » Defeated Dodgers (56-42), 2-1 | Wrigley Field (29-20) | 46-53 | |
| » W: Lee Smith (4-5) L: Bob Welch (8-10) | Fifth | 5½ out |
| Friday, July 29 |
| » Lost to Phillies (49-47), 3-2 | Veteran's Stadium (0-3) | 46-54 | |
| » W: Al Holland (5-0) L: Lee Smith (4-6) | Fifth | 7 out |
| Saturday, July 30 |
| » Defeated Phillies (49-48), 4-3 | Veteran's Stadium (1-3) | 47-54 | |
| » W: Bill Campbell (3-6) L: Willie Hernandez (4-4) S: Lee Smith (15) | Fifth | 7½ out |
| » Lost to Phillies (50-48), 4-3 | Veteran's Stadium (1-4) | 47-55 | |
| » W: Charles Hudson (5-3) L: Steve Trout (8-9) S: Al Holland (11) | Fifth | 7½ out |
| Sunday, July 31 |
| » Lost to Phillies (51-48), 5-2 | Veteran's Stadium (1-5) | 47-56 | Lost 2 |
| » W: John Denny (11-5) L: Dick Ruthven (7-9) S: Willie Hernandez (7) | Fifth | 7 out |
| Monday, August 1 |
| » Lost to Phillies (52-48), 2-1 | Veteran's Stadium (1-6) | 47-57 | Lost 3 |
| » W: Steve Carlton (10-11) L: Bill Campbell (3-7) | Fifth | 7½ out |
| Tuesday, August 2 |
| » Defeated Cardinals (53-51), 5-3 | Busch Stadium II (3-1) | 48-57 | |
| » W: Dickie Noles (4-6) L: Neil Allen (7-10) S: Lee Smith (16) | Fifth | 7½ out |
| Wednesday, August 3 |
| » Defeated Cardinals (53-52), 4-0 | Busch Stadium II (4-1) | 49-57 | Won 2 |
| » W: Chuck Rainey (11-8) L: Bob Forsch (7-9) S: Bill Campbell (7) | Fifth | 7½ out |
| Thursday, August 4 |
| » Defeated Cardinals (53-53), 9-6 | Busch Stadium II (5-1) | 50-57 | Won 3 |
| » W: Steve Trout (9-9) L: Dave LaPoint (9-7) S: Lee Smith (17) | Fifth | 6½ out |
| Friday, August 5 |
| » Lost to Mets (42-66), 9-4 | Wrigley Field (29-21) | 50-58 | |
| » W: Jesse Orosco (9-5) L: Mike Proly (1-4) | Fifth | 6½ out |
| Saturday, August 6 |
| » Lost to Mets (43-66), 4-1 | Wrigley Field (29-22) | 50-59 | Lost 2 |
| » W: Walt Terrell (3-4) L: Fergie Jenkins (3-7) S: Carlos Diaz (1) | Fifth | 7 out |
| Sunday, August 7 |
| » Lost to Mets (44-66), 6-4 | Wrigley Field (29-23) | 50-60 | Lost 3 |
| » W: Doug Sisk (5-3) L: Lee Smith (4-7) S: Jesse Orosco (11) | Fifth | 8 out |
| Tuesday, August 9 |
| » Defeated Cardinals (53-57), 5-3 | Wrigley Field (30-23) | 51-60 | |
| » W: Chuck Rainey (12-8) L: Bob Forsch (7-10) S: Lee Smith (18) | Fifth | 7½ out |
| Wednesday, August 10 |
| » Lost to Cardinals (54-57), 9-5 | Wrigley Field (30-24) | 51-61 | |
| » W: Dave Rucker (4-3) L: Dickie Noles (4-7) S: John Stuper (1) | Fifth | 8½ out |
| Thursday, August 11 |
| » Defeated Cardinals (54-58), 10-5 | Wrigley Field (31-24) | 52-61 | |
| » W: Dick Ruthven (8-9) L: Danny Cox (0-1) | Fifth | 8 out |
| Friday, August 12 |
| » Lost to Mets (46-68), 2-0 | Shea Stadium (2-2) | 52-62 | |
| » W: Walt Terrell (4-4) L: Fergie Jenkins (3-8) | Fifth | 9 out |
| Saturday, August 13 |
| » Lost to Mets (47-68), 5-1 | Shea Stadium (2-3) | 52-63 | Lost 2 |
| » W: Tom Seaver (7-11) L: Rich Bordi (0-1) S: Jesse Orosco (12) | Fifth | 9 out |
| Former Cub Charlie Gilbert dies in New Orleans, LA at the age of 65. |
| Sunday, August 14 |
| » Lost to Mets (48-68), 5-2 | Shea Stadium (2-4) | 52-64 | Lost 3 |
| » W: Ed Lynch (8-7) L: Chuck Rainey (12-9) S: Jesse Orosco (13) | Fifth | 10 out |
| Monday, August 15 |
| » Lost to Phillies (61-52), 5-0 | Wrigley Field (31-25) | 52-65 | Lost 4 |
| » W: Steve Carlton (12-11) L: Steve Trout (9-10) | Fifth | 11 out |
| Tuesday, August 16 |
| » Defeated Phillies (61-53), 10-1 | Wrigley Field (32-25) | 53-65 | |
| » W: Dick Ruthven (9-9) L: Marty Bystrom (5-8) | Fifth | 11 out |
| » Lost to Phillies (62-53), 6-2 | Wrigley Field (32-26) | 53-66 | |
| » W: Willie Hernandez (5-4) L: Mike Proly (1-5) S: Al Holland (14) | Fifth | 11 out |
| Thursday, August 18 |
| » Defeated Braves (71-50), 3-0 | Wrigley Field (33-26) | 54-66 | |
| » W: Fergie Jenkins (4-8) L: Pete Falcone (8-2) S: Lee Smith (19) | Fifth | 10½ out |
| Friday, August 19 |
| » Lost to Braves (72-50), 5-3 | Wrigley Field (33-27) | 54-67 | |
| » W: Phil Niekro (9-7) L: Chuck Rainey (12-10) S: Steve Bedrosian (17) | Fifth | 10½ out |
| Saturday, August 20 |
| » Lost to Braves (73-50), 9-2 | Wrigley Field (33-28) | 54-68 | Lost 2 |
| » W: Ken Dayley (4-3) L: Steve Trout (9-11) S: Terry Forster (11) | Fifth | 10½ out |
| Sunday, August 21 |
| » Lost to Braves (74-50), 11-9 | Wrigley Field (33-29) | 54-69 | Lost 3 |
| » W: Rick Camp (10-9) L: Dick Ruthven (9-10) S: Steve Bedrosian (18) | Fifth | 10½ out |
| Monday, August 22 |
| » Defeated Reds (57-69), 2-0 | Wrigley Field (34-29) | 55-69 | |
| » Manager: Charlie Fox |
| » W: Dickie Noles (5-7) L: Frank Pastore (6-12) S: Lee Smith (20) | Fourth | 9½ out |
| » Major-league debuts: Carmelo Martinez (Cubs) |
| Tuesday, August 23 |
| » Lost to Reds (58-69), 4-2 | Wrigley Field (34-30) | 55-70 | |
| » W: Jeff Russell (2-0) L: Fergie Jenkins (4-9) S: Ben Hayes (6) | Fifth | 9½ out |
| Wednesday, August 24 |
| » Defeated Reds (58-70), 3-0 | Wrigley Field (35-30) | 56-70 | |
| » W: Chuck Rainey (13-10) L: Mario Soto (14-10) | Fifth | 8½ out |
| Friday, August 26 |
| » Lost to Astros (67-60), 1-0 | Astrodome (1-3) | 56-71 | |
| » W: Vern Ruhle (7-3) L: Steve Trout (9-12) S: Bill Dawley (13) | Fourth | 9½ out |
| Saturday, August 27 |
| » Defeated Astros (67-61), 9-5 | Astrodome (2-3) | 57-71 | |
| » W: Dick Ruthven (10-10) L: Joe Niekro (11-11) S: Bill Campbell (8) | Fourth | 9½ out |
| Sunday, August 28 |
| » Lost to Astros (68-61), 4-2 | Astrodome (2-4) | 57-72 | |
| » W: Mike Scott (8-4) L: Dickie Noles (5-8) S: Frank DiPino (13) | Fifth | 9½ out |
| Monday, August 29 |
| » Defeated Braves (76-55), 7-5 | Atlanta-Fulton County Stadium (3-2) | 58-72 | |
| » W: Bill Campbell (4-7) L: Gene Garber (2-4) S: Lee Smith (21) | Fourth | 9½ out |
| Tuesday, August 30 |
| » Defeated Braves (76-56), 9-6 | Atlanta-Fulton County Stadium (4-2) | 59-72 | Won 2 |
| » W: Chuck Rainey (14-10) L: Craig McMurtry (12-9) S: Lee Smith (22) | Fifth | 9½ out |
| Wednesday, August 31 |
| » Lost to Reds (61-73), 6-4 | Riverfront Stadium (0-5) | 59-73 | |
| » W: Rich Gale (4-5) L: Rich Bordi (0-2) S: Ben Hayes (7) | Fifth | 9½ out |
| Thursday, September 1 |
| » Defeated Reds (61-74), 3-1 | Riverfront Stadium (1-5) | 60-73 | |
| » W: Dick Ruthven (11-10) L: Bruce Berenyi (6-14) S: Lee Smith (23) | Fourth | 8½ out |
| » Major-league debuts: Steve Christmas (Reds) |
| Friday, September 2 |
| » Lost to Astros (72-62), 6-5 | Wrigley Field (35-31) | 60-74 | |
| » W: Bill Dawley (6-5) L: Bill Campbell (4-8) S: Frank DiPino (15) | Fourth | 9½ out |
| » Major-league debuts: Dan Rohn (Cubs) |
| Saturday, September 3 |
| » Defeated Astros (72-63), 9-3 | Wrigley Field (36-31) | 61-74 | |
| » W: Fergie Jenkins (5-9) L: Mike Madden (6-4) S: Rich Bordi (1) | Fifth | 9½ out |
| » Major-league debuts: Jeff Heathcock (Astros) |
| Sunday, September 4 |
| » Defeated Astros (72-64), 9-7 | Wrigley Field (37-31) | 62-74 | Won 2 |
| » W: Warren Brusstar (3-1) L: Bill Dawley (6-6) S: Lee Smith (24) | Fifth | 8½ out |
| Monday, September 5 |
| » Lost to Expos (69-66), 7-3 | Stade Olympique (3-4) | 62-75 | |
| » W: Bill Gullickson (14-11) L: Steve Trout (9-13) S: Bob James (3) | Fourth | 8 out |
| Tuesday, September 6 |
| » Lost to Expos (70-66), 8-2 | Stade Olympique (3-5) | 62-76 | Lost 2 |
| » W: Charlie Lea (14-8) L: Dick Ruthven (11-11) S: Scott Sanderson (1) | Fifth | 9 out |
| » Major-league debuts: Dave Owen (Cubs) |
| Wednesday, September 7 |
| » Lost to Expos (71-66), 6-1 | Stade Olympique (3-6) | 62-77 | Lost 3 |
| » W: Steve Rogers (17-9) L: Dickie Noles (5-9) | Fifth | 10 out |
| Friday, September 9 |
| » Lost to Cardinals (71-68), 6-5 | Wrigley Field (37-32) | 62-78 | Lost 4 |
| » W: Bruce Sutter (9-9) L: Lee Smith (4-8) | Fifth | 10½ out |
| » Major-league debuts: Fritzie Connally (Cubs) |
| Saturday, September 10 |
| » Defeated Cardinals (71-69), 8-5 | Wrigley Field (38-32) | 63-78 | |
| » W: Bill Campbell (5-8) L: Jeff Lahti (3-2) S: Lee Smith (25) | Fifth | 10 out |
| Sunday, September 11 |
| » Lost to Cardinals (72-69), 2-1 | Wrigley Field (38-33) | 63-79 | |
| » W: John Stuper (10-10) L: Lee Smith (4-9) S: Bruce Sutter (18) | Fifth | 11 out |
| Monday, September 12 |
| » Defeated Expos (73-68), 8-0 | Wrigley Field (39-33) | 64-79 | |
| » W: Dick Ruthven (12-11) L: Steve Rogers (17-10) | Fifth | 10½ out |
| Tuesday, September 13 |
| » Lost to Expos (74-68), 5-2 | Wrigley Field (39-34) | 64-80 | |
| » W: Bob James (1-0) L: Dickie Noles (5-10) | Fifth | 11 out |
| » Major-league debuts: Don Schulze (Cubs) |
| Wednesday, September 14 |
| » Lost to Pirates (75-70), 6-3 | Three Rivers Stadium (1-7) | 64-81 | Lost 2 |
| » W: John Candelaria (14-8) L: Steve Trout (9-14) | Fifth | 12 out |
| Thursday, September 15 |
| » Lost to Pirates (76-70), 8-4 | Three Rivers Stadium (1-8) | 64-82 | Lost 3 |
| » W: Larry McWilliams (14-6) L: Chuck Rainey (14-11) | Fourth | 12 out |
| » Major-league debuts: Mike Diaz (Cubs) |
| Friday, September 16 |
| » Defeated |