| Sunday, March 9 |
| Former Cub Tom Baker dies in Port Townsend, WA at the age of 46. |
| Thursday, April 10 |
| » Lost to Mets (1-0), 5-2 | Shea Stadium (0-1) | 0-1 | |
| » W: Craig Swan (1-0) L: Rick Reuschel (0-1) S: Neil Allen (1) | Third | 1 out |
| » Major-league debuts: Carlos Lezcano (Cubs) |
| Friday, April 11 |
| » Defeated Mets (1-1), 7-5 | Shea Stadium (1-1) | 1-1 | |
| » W: Dennis Lamp (1-0) L: Ray Burris (0-1) S: Bruce Sutter (1) | Second | ½ out |
| Saturday, April 12 |
| » Defeated Mets (1-2), 6-3 | Shea Stadium (2-1) | 2-1 | Won 2 |
| » W: Mike Krukow (1-0) L: Neil Allen (0-1) S: Bruce Sutter (2) | Second | ½ out |
| Sunday, April 13 |
| » Lost to Mets (2-2), 5-0 | Shea Stadium (2-2) | 2-2 | |
| » W: Pete Falcone (1-0) L: Willie Hernandez (0-1) S: Neil Allen (2) | Third | 1 out |
| Monday, April 14 |
| » Lost to Pirates (4-1), 5-4 | Three Rivers Stadium (0-1) | 2-3 | Lost 2 |
| » W: Kent Tekulve (1-0) L: Bruce Sutter (0-1) | Fourth | 2 out |
| Thursday, April 17 |
| » Defeated Mets (3-4), 4-1 | Wrigley Field (1-0) | 3-3 | |
| » W: Dennis Lamp (2-0) L: Tom Hausman (0-1) S: Bruce Sutter (3) | Third | 1 out |
| Saturday, April 19 |
| » Defeated Mets (3-5), 12-9 | Wrigley Field (2-0) | 4-3 | Won 2 |
| » W: Dick Tidrow (1-0) L: Neil Allen (0-2) S: Bruce Sutter (4) | Second | ½ out |
| Sunday, April 20 |
| » Defeated Mets (3-6), 6-3 | Wrigley Field (3-0) | 5-3 | Won 3 |
| » W: Rick Reuschel (1-1) L: Kevin Kobel (0-1) S: Dick Tidrow (1) | Second | ½ out |
| Tuesday, April 22 |
| » Defeated Cardinals (4-7), 16-12 | Wrigley Field (4-0) | 6-3 | Won 4 |
| » W: Bruce Sutter (1-1) L: Mark Littell (0-1) | Second | 1 out |
| Wednesday, April 23 |
| » Lost to Cardinals (5-7), 3-1 | Wrigley Field (4-1) | 6-4 | |
| » W: Silvio Martinez (1-1) L: Mike Krukow (1-1) | Second | 1 out |
| Friday, April 25 |
| » Defeated Pirates (8-5), 5-3 | Wrigley Field (5-1) | 7-4 | |
| » W: Rick Reuschel (2-1) L: Jim Rooker (2-1) S: Bruce Sutter (5) | First | -- |
| Saturday, April 26 |
| » Lost to Pirates (9-5), 9-2 | Wrigley Field (5-2) | 7-5 | |
| » W: John Candelaria (2-1) L: Dennis Lamp (2-1) | Second | 1 out |
| Monday, April 28 |
| » Defeated Cardinals (7-9), 4-2 | Busch Stadium II (1-0) | 8-5 | |
| » W: Willie Hernandez (1-1) L: Bob Sykes (1-1) S: Bruce Sutter (6) | Second | ½ out |
| Former Cub Bob Porterfield dies in Charlotte, NC at the age of 57. |
| Tuesday, April 29 |
| » Defeated Cardinals (7-10), 6-4 | Busch Stadium II (2-0) | 9-5 | Won 2 |
| » W: Doug Capilla (1-0) L: Bob Sykes (1-2) S: Bruce Sutter (7) | Second | ½ out |
| Wednesday, April 30 |
| » Lost to Cardinals (8-10), 8-2 | Busch Stadium II (2-1) | 9-6 | |
| » W: Pete Vuckovich (4-1) L: Dennis Lamp (2-2) | Second | 1½ out |
| Friday, May 2 |
| » Defeated Reds (13-8), 12-4 | Riverfront Stadium (1-0) | 10-6 | |
| » W: Bruce Sutter (2-1) L: Tom Hume (2-1) | Second | 1 out |
| Saturday, May 3 |
| » Defeated Reds (13-9), 7-1 | Riverfront Stadium (2-0) | 11-6 | Won 2 |
| » W: Mike Krukow (2-1) L: Bill Bonham (1-1) | First | -- |
| Sunday, May 4 |
| » Lost to Reds (14-9), 3-2 | Riverfront Stadium (2-1) | 11-7 | |
| » W: Charlie Leibrandt (2-2) L: Rick Reuschel (2-2) S: Tom Hume (4) | Second | 1½ out |
| » Lost to Reds (15-9), 5-4 | Riverfront Stadium (2-2) | 11-8 | Lost 2 |
| » W: Paul Moskau (1-0) L: Bill Caudill (0-1) S: Doug Bair (2) | Second | 1½ out |
| Tuesday, May 6 |
| » Lost to Padres (12-12), 4-0 | Wrigley Field (5-3) | 11-9 | Lost 3 |
| » W: Randy Jones (2-2) L: Willie Hernandez (1-2) | Second | 2½ out |
| Wednesday, May 7 |
| » Defeated Padres (12-13), 7-4 | Wrigley Field (6-3) | 12-9 | |
| » W: Mike Krukow (3-1) L: Rick Wise (2-2) S: Bruce Sutter (8) | Second | 2½ out |
| Thursday, May 8 |
| » Lost to Padres (13-13), 9-6 | Wrigley Field (6-4) | 12-10 | |
| » W: Bob Shirley (2-1) L: Bruce Sutter (2-2) S: Rollie Fingers (3) | Second | 3 out |
| Friday, May 9 |
| » Lost to Giants (9-19), 6-3 | Wrigley Field (6-5) | 12-11 | Lost 2 |
| » W: Vida Blue (3-2) L: Dennis Lamp (2-3) | Second | 4 out |
| Saturday, May 10 |
| » Defeated Giants (9-20), 15-9 | Wrigley Field (7-5) | 13-11 | |
| » W: Lynn McGlothen (1-0) L: Bob Knepper (2-4) | Second | 4 out |
| Sunday, May 11 |
| » Lost to Giants (10-20), 3-0 | Wrigley Field (7-6) | 13-12 | |
| » W: Ed Whitson (1-5) L: Mike Krukow (3-2) | Second | 4 out |
| Monday, May 12 |
| » Lost to Dodgers (17-12), 2-1 | Dodger Stadium (0-1) | 13-13 | Lost 2 |
| » W: Don Sutton (3-0) L: Rick Reuschel (2-3) S: Bobby Castillo (1) | Third | 4½ out |
| Tuesday, May 13 |
| » Lost to Dodgers (18-12), 4-2 | Dodger Stadium (0-2) | 13-14 | Lost 3 |
| » W: Bob Welch (2-1) L: Dennis Lamp (2-4) | Second | 4½ out |
| Wednesday, May 14 |
| » Defeated Dodgers (18-13), 5-2 | Dodger Stadium (1-2) | 14-14 | |
| » W: Lynn McGlothen (2-0) L: Burt Hooton (3-3) S: Bruce Sutter (9) | Third | 4½ out |
| Friday, May 16 |
| » Lost to Padres (17-16), 3-0 | San Diego/Jack Murphy Stadium (0-1) | 14-15 | |
| » W: Randy Jones (4-2) L: Mike Krukow (3-3) | Third | 5 out |
| Saturday, May 17 |
| » Defeated Padres (17-17), 2-1 | San Diego/Jack Murphy Stadium (1-1) | 15-15 | |
| » W: Rick Reuschel (3-3) L: Eric Rasmussen (1-5) S: Bruce Sutter (10) | Third | 4 out |
| Sunday, May 18 |
| » Lost to Padres (18-17), 4-3 | San Diego/Jack Murphy Stadium (1-2) | 15-16 | |
| » W: Rollie Fingers (4-3) L: Bruce Sutter (2-3) | Fourth | 4 out |
| Tuesday, May 20 |
| » Lost to Giants (15-22), 2-0 | Candlestick Park (0-1) | 15-17 | Lost 2 |
| » W: Ed Whitson (2-5) L: Mike Krukow (3-4) | Fourth | 4½ out |
| Wednesday, May 21 |
| » Lost to Giants (16-22), 4-1 | Candlestick Park (0-2) | 15-18 | Lost 3 |
| » W: Vida Blue (6-2) L: Rick Reuschel (3-4) | Fourth | 6 out |
| Friday, May 23 |
| » Defeated Dodgers (24-14), 2-0 | Wrigley Field (8-6) | 16-18 | |
| » W: Dennis Lamp (3-4) L: Don Sutton (4-1) | Fourth | 5½ out |
| Saturday, May 24 |
| » Lost to Dodgers (25-14), 4-2 | Wrigley Field (8-7) | 16-19 | |
| » W: Bob Welch (4-1) L: Mike Krukow (3-5) S: Rick Sutcliffe (3) | Fourth | 5½ out |
| Sunday, May 25 |
| » Defeated Dodgers (25-15), 2-1 | Wrigley Field (9-7) | 17-19 | |
| » W: Bruce Sutter (3-3) L: Steve Howe (1-2) | Fourth | 4½ out |
| Monday, May 26 |
| » Lost to Expos (20-17), 4-0 | Wrigley Field (9-8) | 17-20 | |
| » W: Steve Rogers (5-4) L: Willie Hernandez (1-3) | Fourth | 4½ out |
| Tuesday, May 27 |
| » Defeated Expos (20-18), 4-2 | Wrigley Field (10-8) | 18-20 | |
| » W: Dennis Lamp (4-4) L: Bill Lee (2-4) S: Dick Tidrow (2) | Fourth | 4½ out |
| Friday, May 30 |
| » Defeated Phillies (22-18), 10-7 | Wrigley Field (11-8) | 19-20 | Won 2 |
| » W: Rick Reuschel (4-4) L: Dan Larson (0-1) | Fourth | 3½ out |
| Saturday, May 31 |
| » Lost to Phillies (23-18), 7-0 | Wrigley Field (11-9) | 19-21 | |
| » W: Steve Carlton (9-2) L: Willie Hernandez (1-4) | Fourth | 4½ out |
| Sunday, June 1 |
| » Defeated Phillies (23-19), 5-4 | Wrigley Field (12-9) | 20-21 | |
| » W: Dick Tidrow (2-0) L: Ron Reed (3-1) S: Bruce Sutter (11) | Fourth | 4½ out |
| Monday, June 2 |
| » Lost to Expos (23-19), 8-7 | Stade Olympique (0-1) | 20-22 | |
| » W: Woodie Fryman (1-1) L: Lynn McGlothen (2-1) | Fourth | 5½ out |
| Tuesday, June 3 |
| » Defeated Expos (23-20), 5-2 | Stade Olympique (1-1) | 21-22 | |
| » W: Rick Reuschel (5-4) L: Ross Grimsley (1-3) | Fourth | 5½ out |
| Wednesday, June 4 |
| » Lost to Expos (24-20), 8-1 | Stade Olympique (1-2) | 21-23 | |
| » W: Steve Rogers (6-5) L: Lynn McGlothen (2-2) | Fourth | 5½ out |
| Thursday, June 5 |
| » Lost to Expos (25-20), 2-0 | Stade Olympique (1-3) | 21-24 | Lost 2 |
| » W: Scott Sanderson (6-3) L: Dennis Lamp (4-5) | Fourth | 6 out |
| Friday, June 6 |
| » Lost to Phillies (25-21), 6-5 | Veteran's Stadium (0-1) | 21-25 | Lost 3 |
| » W: Bob Walk (1-0) L: Mike Krukow (3-6) S: Tug McGraw (4) | Fourth | 6 out |
| Saturday, June 7 |
| » Lost to Phillies (26-21), 5-2 | Veteran's Stadium (0-2) | 21-26 | Lost 4 |
| » W: Randy Lerch (2-7) L: Rick Reuschel (5-5) S: Dickie Noles (4) | Fifth | 6 out |
| Sunday, June 8 |
| » Defeated Phillies (26-22), 2-0 | Veteran's Stadium (1-2) | 22-26 | |
| » W: Lynn McGlothen (3-2) L: Dick Ruthven (5-5) S: Bruce Sutter (12) | Fifth | 6½ out |
| Monday, June 9 |
| » Lost to Astros (31-21), 6-2 | Astrodome (0-1) | 22-27 | |
| » W: Ken Forsch (7-4) L: Dennis Lamp (4-6) | Fifth | 7 out |
| Tuesday, June 10 |
| » Lost to Astros (32-21), 5-2 | Astrodome (0-2) | 22-28 | Lost 2 |
| » W: Vern Ruhle (3-1) L: Mike Krukow (3-7) | Fifth | 8 out |
| Wednesday, June 11 |
| » Lost to Astros (33-21), 3-0 | Astrodome (0-3) | 22-29 | Lost 3 |
| » W: J.R. Richard (8-3) L: Rick Reuschel (5-6) | Fifth | 9 out |
| Friday, June 13 |
| » Lost to Braves (23-31), 7-6 | Wrigley Field (12-10) | 22-30 | Lost 4 |
| » W: Doyle Alexander (4-2) L: Lynn McGlothen (3-3) S: Gene Garber (3) | Fifth | 10½ out |
| Saturday, June 14 |
| » Defeated Braves (23-32), 10-5 | Wrigley Field (13-10) | 23-30 | |
| » W: Dennis Lamp (5-6) L: Phil Niekro (5-9) | Fifth | 9½ out |
| Sunday, June 15 |
| » Defeated Braves (23-33), 4-1 | Wrigley Field (14-10) | 24-30 | Won 2 |
| » W: Mike Krukow (4-7) L: Rick Matula (4-5) S: Bruce Sutter (13) | Fifth | 8½ out |
| Monday, June 16 |
| » Lost to Astros (35-23), 2-1 | Wrigley Field (14-11) | 24-31 | |
| » W: Vern Ruhle (4-1) L: Willie Hernandez (1-5) S: Dave Smith (1) | Fifth | 8½ out |
| Tuesday, June 17 |
| » Lost to Astros (36-23), 7-1 | Wrigley Field (14-12) | 24-32 | Lost 2 |
| » W: J.R. Richard (9-3) L: Lynn McGlothen (3-4) S: Joaquin Andujar (2) | Fifth | 9½ out |
| Wednesday, June 18 |
| » Defeated Reds (33-29), 7-0 | Wrigley Field (15-12) | 25-32 | |
| » W: Dennis Lamp (6-6) L: Charlie Leibrandt (6-4) S: Bruce Sutter (14) | Fifth | 8½ out |
| Thursday, June 19 |
| » Defeated Reds (33-30), 5-2 | Wrigley Field (16-12) | 26-32 | Won 2 |
| » W: Mike Krukow (5-7) L: Tom Hume (3-6) S: Bruce Sutter (15) | Fifth | 7½ out |
| Friday, June 20 |
| » Defeated Braves (27-35), 4-2 | Atlanta-Fulton County Stadium (1-0) | 27-32 | Won 3 |
| » W: Lynn McGlothen (4-4) L: Tommy Boggs (3-3) S: Bruce Sutter (16) | Fourth | 6½ out |
| Saturday, June 21 |
| » Lost to Braves (28-35), 8-0 | Atlanta-Fulton County Stadium (1-1) | 27-33 | |
| » W: Doyle Alexander (5-3) L: Willie Hernandez (1-6) | Fourth | 7½ out |
| Sunday, June 22 |
| » Defeated Braves (28-36), 3-2 | Atlanta-Fulton County Stadium (2-1) | 28-33 | |
| » W: Dennis Lamp (7-6) L: Phil Niekro (5-10) S: Dick Tidrow (3) | Fourth | 7½ out |
| Tuesday, June 24 |
| » Lost to Mets (29-35), 6-5 | Wrigley Field (16-13) | 28-34 | |
| » W: Mark Bomback (5-1) L: Rick Reuschel (5-7) S: Jeff Reardon (2) | Fifth | 8½ out |
| Wednesday, June 25 |
| » Lost to Mets (30-35), 9-1 | Wrigley Field (16-14) | 28-35 | Lost 2 |
| » W: Pat Zachry (2-4) L: Mike Krukow (5-8) | Fifth | 8 out |
| » Defeated Mets (30-36), 4-1 | Wrigley Field (17-14) | 29-35 | |
| » W: Lynn McGlothen (5-4) L: Pete Falcone (3-5) S: Bruce Sutter (17) | Fifth | 8 out |
| Thursday, June 26 |
| » Lost to Mets (31-36), 4-3 | Wrigley Field (17-15) | 29-36 | |
| » W: Ed Glynn (2-1) L: Dick Tidrow (2-1) S: Neil Allen (12) | Fifth | 9 out |
| Friday, June 27 |
| » Lost to Cardinals (29-40), 3-2 | Wrigley Field (17-16) | 29-37 | Lost 2 |
| » W: Kim Seaman (2-0) L: Willie Hernandez (1-7) | Fifth | 9 out |
| Saturday, June 28 |
| » Lost to Cardinals (30-40), 8-6 | Wrigley Field (17-17) | 29-38 | Lost 3 |
| » W: John Littlefield (3-1) L: Bruce Sutter (3-4) | Fifth | 8½ out |
| » Defeated Cardinals (30-41), 2-1 | Wrigley Field (18-17) | 30-38 | |
| » W: Mike Krukow (6-8) L: Jim Otten (0-2) | Fifth | 8½ out |
| Sunday, June 29 |
| » Lost to Cardinals (31-41), 9-7 | Wrigley Field (18-18) | 30-39 | |
| » W: John Urrea (1-0) L: Lynn McGlothen (5-5) S: John Littlefield (2) | Fifth | 9½ out |
| Tuesday, July 1 |
| » Defeated Mets (34-38), 4-3 | Shea Stadium (3-2) | 31-39 | |
| » W: Dennis Lamp (8-6) L: Craig Swan (5-6) S: Bruce Sutter (18) | Fifth | 8 out |
| Wednesday, July 2 |
| » Lost to Mets (35-38), 3-1 | Shea Stadium (3-3) | 31-40 | |
| » W: John Pacella (2-0) L: Rick Reuschel (5-8) S: Neil Allen (14) | Fifth | 9 out |
| Thursday, July 3 |
| » Lost to Pirates (40-35), 5-3 | Three Rivers Stadium (0-2) | 31-41 | Lost 2 |
| » W: Jim Bibby (10-1) L: Mike Krukow (6-9) S: Grant Jackson (4) | Fifth | 9 out |
| Friday, July 4 |
| » Defeated Pirates (40-36), 4-2 | Three Rivers Stadium (1-2) | 32-41 | |
| » W: Lynn McGlothen (6-5) L: Eddie Solomon (4-3) S: Bruce Sutter (19) | Fifth | 8 out |
| » Defeated Pirates (40-37), 2-1 | Three Rivers Stadium (2-2) | 33-41 | Won 2 |
| » W: Doug Capilla (2-0) L: Don Robinson (2-4) S: Dick Tidrow (4) | Fifth | 8 out |
| Saturday, July 5 |
| » Lost to Pirates (41-37), 5-4 | Three Rivers Stadium (2-3) | 33-42 | |
| » W: John Candelaria (5-7) L: Willie Hernandez (1-8) S: Enrique Romo (5) | Fifth | 8 out |
| Former Cub Ben Tincup dies in Claremore, OK at the age of 90. |
| Sunday, July 6 |
| » Lost to Pirates (42-37), 5-4 | Three Rivers Stadium (2-4) | 33-43 | Lost 2 |
| » W: Jim Bibby (11-1) L: Dennis Lamp (8-7) | Fifth | 9 out |
| Thursday, July 10 |
| » Lost to Phillies (42-35), 5-3 | Veteran's Stadium (1-3) | 33-44 | Lost 3 |
| » W: Dick Ruthven (8-5) L: Mike Krukow (6-10) S: Dickie Noles (5) | Fifth | 10 out |
| Friday, July 11 |
| » Lost to Phillies (43-35), 7-2 | Veteran's Stadium (1-4) | 33-45 | Lost 4 |
| » W: Bob Walk (5-0) L: Lynn McGlothen (6-6) S: Ron Reed (5) | Fifth | 10 out |
| Saturday, July 12 |
| » Lost to Expos (44-35), 10-2 | Stade Olympique (1-4) | 33-46 | Lost 5 |
| » W: Scott Sanderson (8-5) L: Rick Reuschel (5-9) | Sixth | 10½ out |
| » Defeated Expos (44-36), 8-6 | Stade Olympique (2-4) | 34-46 | |
| » W: Dick Tidrow (3-1) L: Stan Bahnsen (5-3) S: Bruce Sutter (20) | Sixth | 10½ out |
| Sunday, July 13 |
| » Lost to Expos (45-36), 2-1 | Stade Olympique (2-5) | 34-47 | |
| » W: Stan Bahnsen (6-3) L: Doug Capilla (2-1) | Sixth | 11 out |
| Tuesday, July 15 |
| » Lost to Dodgers (49-37), 6-2 | Wrigley Field (18-19) | 34-48 | Lost 2 |
| » W: Burt Hooton (8-3) L: Lynn McGlothen (6-7) S: Dave Goltz (1) | Sixth | 11 out |
| Wednesday, July 16 |
| » Defeated Dodgers (49-38), 4-1 | Wrigley Field (19-19) | 35-48 | |
| » W: Rick Reuschel (6-9) L: Jerry Reuss (10-3) | Sixth | 11 out |
| Thursday, July 17 |
| » Lost to Dodgers (50-38), 3-1 | Wrigley Field (19-20) | 35-49 | |
| » W: Don Sutton (7-2) L: Dennis Lamp (8-8) | Sixth | 12 out |
| Friday, July 18 |
| » Lost to Padres (38-52), 2-1 | Wrigley Field (19-21) | 35-50 | Lost 2 |
| » W: Bob Shirley (6-6) L: Doug Capilla (2-2) S: Rollie Fingers (11) | Sixth | 13 out |
| Saturday, July 19 |
| » Defeated Padres (38-53), 8-7 | Wrigley Field (20-21) | 36-50 | |
| » W: Bill Caudill (1-1) L: Dennis Kinney (3-2) | Sixth | 12½ out |
| Sunday, July 20 |
| » Defeated Padres (38-54), 6-0 | Wrigley Field (21-21) | 37-50 | Won 2 |
| » W: Lynn McGlothen (7-7) L: Randy Jones (4-9) | Sixth | 12 out |
| » Major-league debuts: Jim Tracy (Cubs) |
| Tuesday, July 22 |
| » Lost to Giants (46-47), 2-0 | Wrigley Field (21-22) | 37-51 | |
| » W: Gary Lavelle (3-5) L: Bill Caudill (1-2) | Sixth | 12½ out |
| » Defeated Giants (46-48), 3-1 | Wrigley Field (22-22) | 38-51 | |
| » W: Dennis Lamp (9-8) L: Bill Bordley (2-1) | Sixth | 12½ out |
| Wednesday, July 23 |
| » Lost to Giants (47-48), 14-6 | Wrigley Field (22-23) | 38-52 | |
| » W: Allen Ripley (4-4) L: Doug Capilla (2-3) | Sixth | 12½ out |
| Friday, July 25 |
| » Lost to Dodgers (52-44), 7-6 | Dodger Stadium (1-3) | 38-53 | Lost 2 |
| » Manager: Joey Amalfitano |
| » W: Steve Howe (4-4) L: Bruce Sutter (3-5) | Sixth | 14 out |
| Saturday, July 26 |
| » Defeated Dodgers (52-45), 5-3 | Dodger Stadium (2-3) | 39-53 | |
| » W: Lynn McGlothen (8-7) L: Jerry Reuss (10-4) S: Bruce Sutter (21) | Sixth | 13 out |
| Sunday, July 27 |
| » Lost to Dodgers (53-45), 3-2 | Dodger Stadium (2-4) | 39-54 | |
| » W: Steve Howe (5-4) L: Bill Caudill (1-3) | Sixth | 14 out |
| Monday, July 28 |
| » Lost to Padres (42-57), 4-2 | San Diego/Jack Murphy Stadium (1-3) | 39-55 | Lost 2 |
| » W: Rollie Fingers (9-7) L: George Riley (0-1) | Sixth | 15 out |
| Tuesday, July 29 |
| » Lost to Padres (43-57), 3-1 | San Diego/Jack Murphy Stadium (1-4) | 39-56 | Lost 3 |
| » W: Randy Jones (5-9) L: Doug Capilla (2-4) | Sixth | 15 out |
| Wednesday, July 30 |
| » Lost to Padres (44-57), 5-2 | San Diego/Jack Murphy Stadium (1-5) | 39-57 | Lost 4 |
| » W: Bob Shirley (7-7) L: Bruce Sutter (3-6) | Sixth | 15 out |
| Friday, August 1 |
| » Defeated Giants (50-52), 5-3 | Candlestick Park (1-2) | 40-57 | |
| » W: Rick Reuschel (7-9) L: Bill Bordley (2-3) S: Bruce Sutter (22) | Sixth | 14 out |
| Saturday, August 2 |
| » Lost to Giants (51-52), 8-5 | Candlestick Park (1-3) | 40-58 | |
| » W: Tom Griffin (3-1) L: Dick Tidrow (3-2) S: Greg Minton (10) | Sixth | 15 out |
| Sunday, August 3 |
| » Defeated Giants (51-53), 3-2 | Candlestick Park (2-3) | 41-58 | |
| » W: Mike Krukow (7-10) L: Allen Ripley (5-5) | Sixth | 14½ out |
| » Defeated Giants (51-54), 3-2 | Candlestick Park (3-3) | 42-58 | Won 2 |
| » W: Dick Tidrow (4-2) L: Bob Knepper (8-14) S: Bruce Sutter (23) | Sixth | 14½ out |
| Tuesday, August 5 |
| » Defeated Pirates (56-48), 11-3 | Wrigley Field (23-23) | 43-58 | Won 3 |
| » W: Rick Reuschel (8-9) L: John Candelaria (7-11) | Sixth | 14½ out |
| Wednesday, August 6 |
| » Lost to Pirates (57-48), 9-7 | Wrigley Field (23-24) | 43-59 | |
| » W: Kent Tekulve (7-5) L: Dick Tidrow (4-3) S: Enrique Romo (7) | Sixth | 16 out |
| » Lost to Pirates (58-48), 2-0 | Wrigley Field (23-25) | 43-60 | Lost 2 |
| » W: Bert Blyleven (6-8) L: Doug Capilla (2-5) S: Grant Jackson (6) | Sixth | 16 out |
| Thursday, August 7 |
| » Lost to Pirates (59-48), 11-3 | Wrigley Field (23-26) | 43-61 | Lost 3 |
| » W: Eddie Solomon (6-3) L: Willie Hernandez (1-9) | Sixth | 16 out |
| Friday, August 8 |
| » Lost to Expos (61-46), 5-2 | Wrigley Field (23-27) | 43-62 | Lost 4 |
| » W: Charlie Lea (4-5) L: Mike Krukow (7-11) S: Woodie Fryman (12) | Sixth | 16 out |
| » Defeated Expos (61-47), 8-4 | Wrigley Field (24-27) | 44-62 | |
| » W: Dennis Lamp (10-8) L: Dale Murray (0-1) | Sixth | 16 out |
| Saturday, August 9 |
| » Defeated Expos (61-48), 3-1 | Wrigley Field (25-27) | 45-62 | Won 2 |
| » W: Rick Reuschel (9-9) L: Steve Rogers (11-7) S: Bruce Sutter (24) | Sixth | 16 out |
| » Lost to Expos (62-48), 4-3 | Wrigley Field (25-28) | 45-63 | |
| » W: Elias Sosa (7-4) L: Bruce Sutter (3-7) | Sixth | 16 out |
| Sunday, August 10 |
| » Lost to Expos (63-48), 7-3 | Wrigley Field (25-29) | 45-64 | Lost 2 |
| » W: Bill Gullickson (4-3) L: Dennis Lamp (10-9) | Fifth | 17 out |
| Tuesday, August 12 |
| » Lost to Phillies (56-52), 8-5 | Wrigley Field (25-30) | 45-65 | Lost 3 |
| » W: Warren Brusstar (1-0) L: George Riley (0-2) | Fifth | 18 out |
| » Lost to Phillies (57-52), 5-2 | Wrigley Field (25-31) | 45-66 | Lost 4 |
| » W: Steve Carlton (18-6) L: Mike Krukow (7-12) | Fifth | 18 out |
| Wednesday, August 13 |
| » Defeated Phillies (57-53), 2-1 | Wrigley Field (26-31) | 46-66 | |
| » W: Dick Tidrow (5-3) L: Dick Ruthven (10-8) | Fifth | 17 out |
| Thursday, August 14 |
| » Lost to Cardinals (51-61), 10-9 | Busch Stadium II (2-2) | 46-67 | |
| » W: Jim Kaat (5-6) L: George Riley (0-3) | Fifth | 17½ out |
| Friday, August 15 |
| » Defeated Cardinals (51-62), 5-4 | Busch Stadium II (3-2) | 47-67 | |
| » W: Lynn McGlothen (9-7) L: Silvio Martinez (4-6) S: Bruce Sutter (25) | Sixth | 17½ out |
| Saturday, August 16 |
| » Defeated Cardinals (51-63), 9-4 | Busch Stadium II (4-2) | 48-67 | Won 2 |
| » W: Mike Krukow (8-12) L: Bob Sykes (6-9) S: Bruce Sutter (26) | Sixth | 17½ out |
| Sunday, August 17 |
| » Defeated Cardinals (51-64), 6-2 | Busch Stadium II (5-2) | 49-67 | Won 3 |
| » W: Rick Reuschel (10-9) L: John Fulgham (3-6) | Sixth | 17 out |
| Tuesday, August 19 |
| » Lost to Braves (56-62), 5-4 | Atlanta-Fulton County Stadium (2-2) | 49-68 | |
| » W: Phil Niekro (10-14) L: Dick Tidrow (5-4) | Sixth | 17 out |
| Wednesday, August 20 |
| » Lost to Braves (57-62), 9-5 | Atlanta-Fulton County Stadium (2-3) | 49-69 | Lost 2 |
| » W: Larry McWilliams (9-9) L: Lynn McGlothen (9-8) | Sixth | 17 out |
| Thursday, August 21 |
| » Lost to Braves (58-62), 6-4 | Atlanta-Fulton County Stadium (2-4) | 49-70 | Lost 3 |
| » W: Phil Niekro (11-14) L: Mike Krukow (8-13) S: Rick Camp (10) | Sixth | 17 out |
| Friday, August 22 |
| » Lost to Astros (68-53), 3-2 | Astrodome (0-4) | 49-71 | Lost 4 |
| » W: Frank LaCorte (8-3) L: Bill Caudill (1-4) | Sixth | 18 out |
| Saturday, August 23 |
| » Lost to Astros (69-53), 1-0 | Astrodome (0-5) | 49-72 | Lost 5 |
| » W: Joe Niekro (13-11) L: George Riley (0-4) | Sixth | 19 out |
| Sunday, August 24 |
| » Lost to Astros (70-53), 2-1 | Astrodome (0-6) | 49-73 | Lost 6 |
| » W: Nolan Ryan (9-8) L: Bill Caudill (1-5) | Sixth | 20 out |
| Monday, August 25 |
| » Lost to Reds (67-58), 2-0 | Riverfront Stadium (2-3) | 49-74 | Lost 7 |
| » W: Tom Seaver (5-7) L: Lynn McGlothen (9-9) S: Mario Soto (1) | Sixth | 20 out |
| Tuesday, August 26 |
| » Defeated Reds (67-59), 4-2 | Riverfront Stadium (3-3) | 50-74 | |
| » W: Rick Reuschel (11-9) L: Tom Hume (7-8) | Sixth | 19 out |
| » Major-league debuts: Paul Householder (Reds) |
| Future Cub Brendan Harris is born in Albany, NY. |
| Thursday, August 28 |
| » Lost to Astros (72-55), 4-1 | Wrigley Field (26-32) | 50-75 | |
| » W: Joaquin Andujar (2-4) L: Dennis Lamp (10-10) S: Joe Sambito (13) | Sixth | 18½ out |
| Friday, August 29 |
| » Lost to Astros (73-55), 6-5 | Wrigley Field (26-33) | 50-76 | Lost 2 |
| » W: Dave Smith (4-5) L: Dick Tidrow (5-5) S: Frank LaCorte (10) | Sixth | 18½ out |
| Saturday, August 30 |
| » Lost to Astros (74-55), 2-0 | Wrigley Field (26-34) | 50-77 | Lost 3 |
| » W: Vern Ruhle (8-3) L: Lynn McGlothen (9-10) | Sixth | 18½ out |
| Sunday, August 31 |
| » Defeated Astros (74-56), 8-7 | Wrigley Field (27-34) | 51-77 | |
| » W: Dick Tidrow (6-5) L: Frank LaCorte (8-4) | Sixth | 17½ out |
| Monday, September 1 |
| » Lost to Braves (66-65), 5-2 | Wrigley Field (27-35) | 51-78 | |
| » W: Rick Matula (9-12) L: Dennis Lamp (10-11) S: Rick Camp (12) | Sixth | 18 out |
| » Major-league debuts: Lee Smith (Cubs) |
| Tuesday, September 2 |
| » Lost to Braves (67-65), 10-5 | Wrigley Field (27-36) | 51-79 | Lost 2 |
| » W: Doyle Alexander (13-7) L: Mike Krukow (8-14) | Sixth | 19 out |
| Wednesday, September 3 |
| » Lost to Braves (68-65), 4-3 | Wrigley Field (27-37) | 51-80 | Lost 3 |
| » W: Tommy Boggs (9-8) L: Lynn McGlothen (9-11) S: Rick Camp (13) | Sixth | 20 out |
| Thursday, September 4 |
| » Major-league debuts: Hubie Brooks (Mets) |
| Friday, September 5 |
| » Lost to Reds (73-61), 5-3 | Wrigley Field (27-38) | 51-81 | Lost 4 |
| » W: Tom Seaver (7-7) L: Rick Reuschel (11-10) S: Mario Soto (3) | Sixth | 20½ out |
| Saturday, September 6 |
| » Defeated Reds (73-62), 4-3 | Wrigley Field (28-38) | 52-81 | |
| » W: Bruce Sutter (4-7) L: Tom Hume (7-10) | Sixth | 21 out |
| » Lost to Reds (74-62), 6-1 | Wrigley Field (28-39) | 52-82 | |
| » W: Joe Price (6-2) L: Randy Martz (0-1) S: Mario Soto (4) | Sixth | 21 out |
| » Major-league debuts: Randy Martz (Cubs) |
| Sunday, September 7 |
| » Defeated Reds (74-63), 6-4 | Wrigley Field (29-39) | 53-82 | |
| » W: Bruce Sutter (5-7) L: Doug Bair (1-6) | Sixth | 20 out |
| Future Cub Mark Prior is born in San Diego, CA. |
| Monday, September 8 |
| » Defeated Cardinals (61-75), 6-2 | Busch Stadium II (6-2) | 54-82 | Won 2 |
| » W: Lynn McGlothen (10-11) L: Bob Forsch (11-8) | Sixth | 19½ out |
| Tuesday, September 9 |
| » Lost to Cardinals (62-75), 6-4 | Busch Stadium II (6-3) | 54-83 | |
| » W: Silvio Martinez (5-9) L: Doug Capilla (2-6) S: Kim Seaman (3) | Sixth | 20½ out |
| Wednesday, September 10 |
| » Lost to Expos (76-63), 4-2 | Stade Olympique (2-6) | 54-84 | Lost 2 |
| » W: Bill Gullickson (8-4) L: Rick Reuschel (11-11) | Sixth | 21½ out |
| Thursday, September 11 |
| » Lost to Expos (77-63), 6-5 | Stade Olympique (2-7) | 54-85 | Lost 3 |
| » W: Woodie Fryman (6-4) L: Randy Martz (0-2) | Sixth | 22½ out |
| Friday, September 12 |
| » Defeated Mets (59-82), 10-5 | Shea Stadium (4-3) | 55-85 | |
| » W: Lee Smith (1-0) L: Tom Hausman (6-5) | Sixth | 22½ out |
| Saturday, September 13 |
| » Lost to Mets (60-82), 4-2 | Shea Stadium (4-4) | 55-86 | |
| » W: Ed Lynch (1-0) L: Lynn McGlothen (10-12) S: Roy Lee Jackson (1) | Sixth | 22½ out |
| Sunday, September 14 |
| » Lost to Mets (61-82), 10-7 | Shea Stadium (4-5) | 55-87 | Lost 2 |
| » W: Neil Allen (6-8) L: Bruce Sutter (5-8) | Sixth | 23½ out |
| Monday, September 15 |
| » Lost to Cardinals (65-79), 5-1 | Wrigley Field (29-40) | 55-88 | Lost 3 |
| » W: Andy Rincon (1-0) L: Doug Capilla (2-7) | Sixth | 24 out |
| » Major-league debuts: Andy Rincon (Cardinals) |
| Tuesday, September 16 |
| » Defeated Cardinals (65-80), 6-5 | Wrigley Field (30-40) | 56-88 | |
| » W: Bill Caudill (2-5) L: John Littlefield (5-4) | Sixth | 24½ out |
| Wednesday, September 17 |
| » Lost to Cardinals (66-80), 8-5 | Wrigley Field (30-41) | 56-89 | |
| » W: Pete Vuckovich (12-9) L: Mike Krukow (8-15) | Sixth | 24½ out |
| Friday, September 19 |
| » Defeated Phillies (79-67), 4-3 | Wrigley Field (31-41) | 57-89 | |
| » W: Lee Smith (2-0) L: Warren Brusstar (2-1) | Sixth | 23½ out |
| Saturday, September 20 |
| » Lost to Phillies (80-67), 7-3 | Wrigley Field (31-42) | 57-90 | |
| » W: Marty Bystrom (3-0) L: Lynn McGlothen (10-13) | Sixth | 24½ out |
| Sunday, September 21 |
| » Lost to Phillies (81-67), 7-3 | Wrigley Field (31-43) | 57-91 | Lost 2 |
| » W: Dick Ruthven (16-10) L: Dennis Lamp (10-12) S: Ron Reed (9) | Sixth | 24½ out |
| Monday, September 22 |
| » Defeated Mets (63-87), 3-2 | Wrigley Field (32-43) | 58-91 | |
| » W: Bill Caudill (3-5) L: Dyar Miller (1-2) S: Bruce Sutter (27) | Sixth | 24 out |
| Tuesday, September 23 |
| » Defeated Mets (63-88), 6-5 | Wrigley Field (33-43) | 59-91 | Won 2 |
| » W: Mike Krukow (9-15) L: Mike Scott (0-1) S: Bruce Sutter (28) | Sixth | 23½ out |
| Wednesday, September 24 |
| » Lost to Expos (84-68), 8-4 | Wrigley Field (33-44) | 59-92 | |
| » W: Charlie Lea (6-5) L: Rick Reuschel (11-12) S: Stan Bahnsen (4) | Sixth | 24½ out |
| Thursday, September 25 |
| » Defeated Expos (84-69), 5-4 | Wrigley Field (34-44) | 60-92 | |
| » W: Lynn McGlothen (11-13) L: Bill Gullickson (9-5) S: Dick Tidrow (5) | Sixth | 24 out< |