| Friday, January 13 |
| Former Cub Merwin Jacobson dies in Baltimore, MD at the age of 84. |
| Tuesday, March 7 |
| Former Cub Steve Bilko dies in Wilkes-Barre, PA at the age of 50. |
| Sunday, March 12 |
| Former Cub Alex McCarthy dies in Salisbury, MD at the age of 90. |
| Monday, March 27 |
| Former Cub Dutch Zwilling dies in LaCrescenta, CA at the age of 90. |
| Monday, April 3 |
| Future Cub Bobby Hill is born in San Jose, CA. |
| Wednesday, April 5 |
| » Major-league debuts: Hosken Powell (Twins) |
| Friday, April 7 |
| » Lost to Pirates (1-0), 1-0 | Three Rivers Stadium (0-1) | 0-1 | |
| » W: John Candelaria (1-0) L: Rick Reuschel (0-1) | Second | 1 out |
| Saturday, April 8 |
| » Lost to Pirates (2-0), 4-3 | Three Rivers Stadium (0-2) | 0-2 | Lost 2 |
| » W: Jim Bibby (1-0) L: Bruce Sutter (0-1) | Third | 2 out |
| Sunday, April 9 |
| » Defeated Pirates (2-1), 4-3 | Three Rivers Stadium (1-2) | 1-2 | |
| » W: Donnie Moore (1-0) L: Bruce Kison (0-1) S: Bruce Sutter (1) | Third | 1½ out |
| Monday, April 10 |
| » Lost to Mets (4-1), 6-0 | Shea Stadium (0-1) | 1-3 | |
| » W: Craig Swan (1-0) L: Dennis Lamp (0-1) | Fourth | 2½ out |
| Tuesday, April 11 |
| » Defeated Mets (4-2), 4-2 | Shea Stadium (1-1) | 2-3 | |
| » W: Rick Reuschel (1-1) L: Jerry Koosman (1-1) S: Donnie Moore (1) | Fourth | 1½ out |
| Wednesday, April 12 |
| » Defeated Mets (4-3), 4-2 | Shea Stadium (2-1) | 3-3 | Won 2 |
| » W: Ray Burris (1-0) L: Nino Espinosa (0-1) | Fourth | ½ out |
| Friday, April 14 |
| » Defeated Pirates (2-5), 5-4 | Wrigley Field (1-0) | 4-3 | Won 3 |
| » W: Willie Hernandez (1-0) L: Jim Bibby (1-1) | Third | ½ out |
| Saturday, April 15 |
| » Lost to Pirates (3-5), 13-10 | Wrigley Field (1-1) | 4-4 | |
| » W: Jim Rooker (1-1) L: Dennis Lamp (0-2) | Third | 1 out |
| Sunday, April 16 |
| » Defeated Pirates (3-6), 5-1 | Wrigley Field (2-1) | 5-4 | |
| » W: Rick Reuschel (2-1) L: Don Robinson (0-1) | Second | 1 out |
| Tuesday, April 18 |
| » Defeated Expos (4-5), 2-1 | Wrigley Field (3-1) | 6-4 | Won 2 |
| » W: Ray Burris (2-0) L: Steve Rogers (1-2) S: Bruce Sutter (2) | Second | 1 out |
| Wednesday, April 19 |
| » Lost to Expos (5-5), 8-6 | Wrigley Field (3-2) | 6-5 | |
| » W: Darold Knowles (1-0) L: Bruce Sutter (0-2) | Third | 1½ out |
| Friday, April 21 |
| » Defeated Mets (8-6), 5-0 | Wrigley Field (4-2) | 7-5 | |
| » W: Dennis Lamp (1-2) L: Craig Swan (1-1) | Second | 2 out |
| Saturday, April 22 |
| » Lost to Mets (9-6), 3-2 | Wrigley Field (4-3) | 7-6 | |
| » W: Mardie Cornejo (3-0) L: Rick Reuschel (2-2) S: Skip Lockwood (4) | Third | 1 out |
| Sunday, April 23 |
| » Defeated Mets (9-7), 3-2 | Wrigley Field (5-3) | 8-6 | |
| » W: Willie Hernandez (2-0) L: Butch Metzger (0-1) | Second | ½ out |
| Monday, April 24 |
| » Lost to Phillies (6-6), 12-2 | Veteran's Stadium (0-1) | 8-7 | |
| » W: Randy Lerch (2-1) L: Woodie Fryman (0-1) | Second | 1½ out |
| Tuesday, April 25 |
| » Lost to Phillies (7-6), 7-0 | Veteran's Stadium (0-2) | 8-8 | Lost 2 |
| » W: Jim Kaat (1-0) L: Dennis Lamp (1-3) | Fourth | 1½ out |
| Wednesday, April 26 |
| » Defeated Phillies (7-7), 4-2 | Veteran's Stadium (1-2) | 9-8 | |
| » W: Rick Reuschel (3-2) L: Steve Carlton (1-3) S: Bruce Sutter (3) | Second | ½ out |
| Friday, April 28 |
| » Defeated Braves (5-13), 4-3 | Atlanta-Fulton County Stadium (1-0) | 10-8 | Won 2 |
| » W: Bruce Sutter (1-2) L: Dave Campbell (0-1) S: Donnie Moore (2) | Second | ½ out |
| Saturday, April 29 |
| » Lost to Braves (6-13), 5-0 | Atlanta-Fulton County Stadium (1-1) | 10-9 | |
| » W: Phil Niekro (2-4) L: Woodie Fryman (0-2) | Third | 1½ out |
| Sunday, April 30 |
| » Defeated Braves (6-14), 7-5 | Atlanta-Fulton County Stadium (2-1) | 11-9 | |
| » W: Bruce Sutter (2-2) L: Adrian Devine (1-1) | Third | 1½ out |
| Tuesday, May 2 |
| » Defeated Dodgers (13-8), 5-4 | Wrigley Field (6-3) | 12-9 | Won 2 |
| » W: Bruce Sutter (3-2) L: Mike Garman (0-1) | Third | 1½ out |
| Wednesday, May 3 |
| » Lost to Dodgers (14-8), 9-5 | Wrigley Field (6-4) | 12-10 | |
| » W: Doug Rau (4-0) L: Ray Burris (2-1) S: Terry Forster (3) | Third | 1 out |
| Thursday, May 4 |
| » Lost to Dodgers (15-8), 4-1 | Wrigley Field (6-5) | 12-11 | Lost 2 |
| » W: Rick Rhoden (4-0) L: Woodie Fryman (0-3) | Third | 1½ out |
| Saturday, May 6 |
| » Lost to Giants (13-11), 2-1 | Wrigley Field (6-6) | 12-12 | Lost 3 |
| » W: Randy Moffitt (2-1) L: Willie Hernandez (2-1) S: Gary Lavelle (3) | Third | 2½ out |
| Sunday, May 7 |
| » Lost to Giants (14-11), 2-1 | Wrigley Field (6-7) | 12-13 | Lost 4 |
| » W: Vida Blue (4-1) L: Ray Burris (2-2) S: Gary Lavelle (4) | Fourth | 3½ out |
| Tuesday, May 9 |
| » Defeated Padres (10-16), 8-5 | San Diego/Jack Murphy Stadium (1-0) | 13-13 | |
| » W: Woodie Fryman (1-3) L: Bob Shirley (0-4) | Third | 2½ out |
| Wednesday, May 10 |
| » Lost to Padres (11-16), 1-0 | San Diego/Jack Murphy Stadium (1-1) | 13-14 | |
| » W: Randy Jones (3-2) L: Dennis Lamp (1-4) | Fourth | 3½ out |
| Thursday, May 11 |
| » Defeated Padres (11-17), 4-3 | San Diego/Jack Murphy Stadium (2-1) | 14-14 | |
| » W: Willie Hernandez (3-1) L: Mark Lee (0-1) S: Donnie Moore (3) | Third | 3½ out |
| Friday, May 12 |
| » Defeated Dodgers (17-13), 9-7 | Dodger Stadium (1-0) | 15-14 | Won 2 |
| » W: Donnie Moore (2-0) L: Don Sutton (2-4) S: Bruce Sutter (4) | Third | 2½ out |
| Saturday, May 13 |
| » Lost to Dodgers (18-13), 5-2 | Dodger Stadium (1-1) | 15-15 | |
| » W: Tommy John (5-1) L: Woodie Fryman (1-4) S: Terry Forster (5) | Third | 2½ out |
| Sunday, May 14 |
| » Defeated Dodgers (18-14), 10-7 | Dodger Stadium (2-1) | 16-15 | |
| » W: Paul Reuschel (1-0) L: Rick Rhoden (4-2) | Third | 2½ out |
| Tuesday, May 16 |
| » Lost to Giants (21-12), 4-3 | Candlestick Park (0-1) | 16-16 | |
| » W: Bob Knepper (5-1) L: Rick Reuschel (3-3) | Third | 2 out |
| Wednesday, May 17 |
| » Lost to Giants (22-12), 9-5 | Candlestick Park (0-2) | 16-17 | Lost 2 |
| » W: Vida Blue (6-1) L: Ray Burris (2-3) | Third | 2 out |
| Friday, May 19 |
| » Defeated Cardinals (14-24), 6-2 | Wrigley Field (7-7) | 17-17 | |
| » W: Dave Roberts (1-0) L: John Denny (3-2) | Third | 1½ out |
| Saturday, May 20 |
| » Defeated Cardinals (14-25), 10-2 | Wrigley Field (8-7) | 18-17 | Won 2 |
| » W: Woodie Fryman (2-4) L: Pete Falcone (0-2) S: Donnie Moore (4) | Second | 1½ out |
| Former Cub Bob Logan dies in Indianapolis, IN at the age of 69. |
| Sunday, May 21 |
| » Defeated Cardinals (14-26), 3-2 | Wrigley Field (9-7) | 19-17 | Won 3 |
| » W: Rick Reuschel (4-3) L: Mark Littell (1-6) S: Bruce Sutter (5) | Second | ½ out |
| Wednesday, May 24 |
| » Defeated Phillies (19-17), 6-4 | Wrigley Field (10-7) | 20-17 | Won 4 |
| » W: Bruce Sutter (4-2) L: Gene Garber (2-1) | First | -- |
| Thursday, May 25 |
| » Defeated Phillies (19-18), 5-1 | Wrigley Field (11-7) | 21-17 | Won 5 |
| » W: Rick Reuschel (5-3) L: Steve Carlton (4-5) S: Bruce Sutter (6) | First | -- |
| Friday, May 26 |
| » Defeated Cardinals (15-29), 6-0 | Busch Stadium II (1-0) | 22-17 | Won 6 |
| » W: Dave Roberts (2-0) L: Pete Falcone (0-3) | First | -- |
| Saturday, May 27 |
| » Defeated Cardinals (15-30), 3-2 | Busch Stadium II (2-0) | 23-17 | Won 7 |
| » W: Willie Hernandez (4-1) L: Buddy Schultz (0-1) | First | -- |
| Sunday, May 28 |
| » Defeated Cardinals (15-31), 2-0 | Busch Stadium II (3-0) | 24-17 | Won 8 |
| » W: Ray Burris (3-3) L: John Denny (4-3) | First | -- |
| Monday, May 29 |
| » Lost to Expos (23-22), 4-2 | Stade Olympique (0-1) | 24-18 | |
| » W: Ross Grimsley (8-2) L: Donnie Moore (2-1) | First | -- |
| Former Cub Carl Reynolds dies in Houston, TX at the age of 76. |
| Tuesday, May 30 |
| » Lost to Expos (24-22), 7-4 | Stade Olympique (0-2) | 24-19 | Lost 2 |
| » W: Steve Rogers (6-5) L: Rick Reuschel (5-4) S: Mike Garman (2) | First | -- |
| Wednesday, May 31 |
| » Lost to Expos (25-22), 9-1 | Stade Olympique (0-3) | 24-20 | Lost 3 |
| » W: Rudy May (5-5) L: Dennis Lamp (1-5) | First | -- |
| Friday, June 2 |
| » Defeated Braves (18-28), 2-1 | Wrigley Field (12-7) | 25-20 | |
| » W: Donnie Moore (3-1) L: Jamie Easterly (1-3) | First | -- |
| Saturday, June 3 |
| » Defeated Braves (18-29), 8-6 | Wrigley Field (13-7) | 26-20 | Won 2 |
| » W: Donnie Moore (4-1) L: Jamie Easterly (1-4) S: Bruce Sutter (7) | First | -- |
| Future Cub Steve Smyth is born in Brawley, CA. Former Cub Marv Rickert dies in Oakville, WA at the age of 58. |
| Sunday, June 4 |
| » Defeated Braves (18-30), 6-4 | Wrigley Field (14-7) | 27-20 | Won 3 |
| » W: Rick Reuschel (6-4) L: Mickey Mahler (0-2) | First | -- |
| Monday, June 5 |
| » Defeated Astros (22-28), 2-1 | Wrigley Field (15-7) | 28-20 | Won 4 |
| » W: Willie Hernandez (5-1) L: Mark Lemongello (5-6) | First | -- |
| Tuesday, June 6 |
| » Defeated Astros (22-29), 9-4 | Wrigley Field (16-7) | 29-20 | Won 5 |
| » W: Dave Roberts (3-0) L: Joaquin Andujar (3-3) | First | -- |
| Wednesday, June 7 |
| » Lost to Reds (34-21), 9-6 | Wrigley Field (16-8) | 29-21 | |
| » W: Bill Bonham (7-0) L: Ray Burris (3-4) S: Doug Bair (9) | First | -- |
| Thursday, June 8 |
| » Defeated Reds (34-22), 10-1 | Wrigley Field (17-8) | 30-21 | |
| » W: Rick Reuschel (7-4) L: Fred Norman (6-3) | First | -- |
| Friday, June 9 |
| » Defeated Padres (23-31), 5-0 | Wrigley Field (18-8) | 31-21 | Won 2 |
| » W: Dennis Lamp (2-5) L: Bob Owchinko (3-6) | First | -- |
| Saturday, June 10 |
| » Lost to Padres (24-31), 10-8 | Wrigley Field (18-9) | 31-22 | |
| » W: Gaylord Perry (5-2) L: Donnie Moore (4-2) S: Rollie Fingers (14) | Second | 1 out |
| Sunday, June 11 |
| » Defeated Padres (24-32), 7-4 | Wrigley Field (19-9) | 32-22 | |
| » W: Ray Burris (4-4) L: Bob Shirley (3-7) S: Bruce Sutter (8) | First | -- |
| Monday, June 12 |
| » Defeated Reds (35-25), 3-2 | Riverfront Stadium (1-0) | 33-22 | Won 2 |
| » W: Rick Reuschel (8-4) L: Bill Bonham (7-1) S: Ken Holtzman (1) | First | -- |
| Tuesday, June 13 |
| » Lost to Reds (36-25), 1-0 | Riverfront Stadium (1-1) | 33-23 | |
| » W: Fred Norman (7-3) L: Dennis Lamp (2-6) S: Doug Bair (10) | First | -- |
| » Major-league debuts: Dave Geisel (Cubs) |
| Wednesday, June 14 |
| » Lost to Reds (37-25), 3-1 | Riverfront Stadium (1-2) | 33-24 | Lost 2 |
| » W: Manny Sarmiento (6-3) L: Dave Roberts (3-1) S: Doug Bair (11) | First | -- |
| Friday, June 16 |
| » Defeated Astros (26-32), 7-6 | Astrodome (1-0) | 34-24 | |
| » W: Paul Reuschel (2-0) L: Rick Williams (1-1) | First | -- |
| Saturday, June 17 |
| » Lost to Astros (27-32), 5-4 | Astrodome (1-1) | 34-25 | |
| » W: Joe Niekro (3-4) L: Willie Hernandez (5-2) | First | -- |
| Sunday, June 18 |
| » Lost to Astros (28-32), 3-1 | Astrodome (1-2) | 34-26 | Lost 2 |
| » W: Tom Dixon (3-2) L: Dennis Lamp (2-7) S: Joe Sambito (5) | First | -- |
| Monday, June 19 |
| » Defeated Pirates (29-33), 6-4 | Three Rivers Stadium (2-2) | 35-26 | |
| » W: Bruce Sutter (5-2) L: Grant Jackson (2-3) S: Willie Hernandez (1) | First | -- |
| Tuesday, June 20 |
| » Lost to Pirates (30-33), 6-1 | Three Rivers Stadium (2-3) | 35-27 | |
| » W: Bert Blyleven (6-5) L: Ken Holtzman (1-1) | First | -- |
| Wednesday, June 21 |
| » Lost to Pirates (31-33), 2-1 | Three Rivers Stadium (2-4) | 35-28 | Lost 2 |
| » W: John Candelaria (7-6) L: Ray Burris (4-5) | First | -- |
| Friday, June 23 |
| » Lost to Phillies (33-29), 6-1 | Veteran's Stadium (1-3) | 35-29 | Lost 3 |
| » W: Dick Ruthven (3-7) L: Dave Roberts (3-2) | Second | 1 out |
| » Lost to Phillies (34-29), 6-1 | Veteran's Stadium (1-4) | 35-30 | Lost 4 |
| » W: Jim Lonborg (6-5) L: Dennis Lamp (2-8) | Second | 1 out |
| Saturday, June 24 |
| » Lost to Phillies (35-29), 6-2 | Veteran's Stadium (1-5) | 35-31 | Lost 5 |
| » W: Jim Kaat (4-1) L: Ken Holtzman (1-2) S: Ron Reed (4) | Second | 1 out |
| Sunday, June 25 |
| » Lost to Phillies (36-29), 4-2 | Veteran's Stadium (1-6) | 35-32 | Lost 6 |
| » W: Larry Christenson (5-6) L: Rick Reuschel (8-5) | Second | 2 out |
| Monday, June 26 |
| » Defeated Mets (31-43), 10-9 | Wrigley Field (20-9) | 36-32 | |
| » W: Lynn McGlothen (1-0) L: Butch Metzger (1-2) S: Bruce Sutter (9) | Second | 1 out |
| Tuesday, June 27 |
| » Lost to Mets (32-43), 7-2 | Wrigley Field (20-10) | 36-33 | |
| » W: Pat Zachry (9-3) L: Dennis Lamp (2-9) | Second | 2 out |
| Wednesday, June 28 |
| » Defeated Mets (32-44), 9-8 | Wrigley Field (21-10) | 37-33 | |
| » W: Ray Burris (5-5) L: Butch Metzger (1-3) | Second | 2 out |
| Former Cub Johnny Schulte dies in St.Louis, MO at the age of 82. |
| Thursday, June 29 |
| » Lost to Phillies (39-30), 9-3 | Wrigley Field (21-11) | 37-34 | |
| » W: Jim Kaat (5-1) L: Dave Roberts (3-3) S: Tug McGraw (5) | Second | 3 out |
| Friday, June 30 |
| » Defeated Phillies (39-31), 2-0 | Wrigley Field (22-11) | 38-34 | |
| » W: Mike Krukow (1-0) L: Larry Christenson (5-7) | Second | 3 out |
| » Lost to Phillies (40-31), 6-5 | Wrigley Field (22-12) | 38-35 | |
| » W: Tug McGraw (7-3) L: Bruce Sutter (5-3) | Second | 3 out |
| Saturday, July 1 |
| » Lost to Phillies (41-31), 2-1 | Wrigley Field (22-13) | 38-36 | Lost 2 |
| » W: Randy Lerch (4-6) L: Dennis Lamp (2-10) S: Ron Reed (5) | Second | 4 out |
| Sunday, July 2 |
| » Lost to Phillies (42-31), 6-5 | Wrigley Field (22-14) | 38-37 | Lost 3 |
| » W: Dick Ruthven (5-7) L: Ken Holtzman (1-3) S: Tug McGraw (6) | Second | 5 out |
| Monday, July 3 |
| » Defeated Cardinals (32-49), 6-2 | Busch Stadium II (4-0) | 39-37 | |
| » W: Dave Roberts (4-3) L: Pete Falcone (1-6) S: Bruce Sutter (10) | Second | 4½ out |
| Tuesday, July 4 |
| » Defeated Cardinals (32-50), 7-5 | Busch Stadium II (5-0) | 40-37 | Won 2 |
| » W: Dave Geisel (1-0) L: George Frazier (0-2) S: Bruce Sutter (11) | Second | 4 out |
| Wednesday, July 5 |
| » Defeated Cardinals (32-51), 5-1 | Busch Stadium II (6-0) | 41-37 | Won 3 |
| » W: Mike Krukow (2-0) L: Bob Forsch (9-7) S: Bruce Sutter (12) | Second | 4 out |
| Thursday, July 6 |
| » Lost to Mets (35-48), 9-6 | Shea Stadium (2-2) | 41-38 | |
| » W: Nino Espinosa (7-7) L: Lynn McGlothen (1-1) S: Skip Lockwood (9) | Second | 5 out |
| Friday, July 7 |
| » Defeated Mets (35-49), 9-7 | Shea Stadium (3-2) | 42-38 | |
| » W: Lynn McGlothen (2-1) L: Paul Siebert (0-2) S: Bruce Sutter (13) | Second | 4 out |
| Saturday, July 8 |
| » Lost to Mets (36-49), 7-0 | Shea Stadium (3-3) | 42-39 | |
| » W: Kevin Kobel (1-1) L: Ray Burris (5-6) | Second | 4½ out |
| Sunday, July 9 |
| » Defeated Mets (36-50), 4-1 | Shea Stadium (4-3) | 43-39 | |
| » W: Mike Krukow (3-0) L: Pat Zachry (10-4) S: Bruce Sutter (14) | Second | 4½ out |
| Thursday, July 13 |
| » Lost to Padres (43-45), 5-2 | Wrigley Field (22-15) | 43-40 | |
| » W: Gaylord Perry (10-4) L: Rick Reuschel (8-6) S: John D'Acquisto (8) | Second | 5 out |
| Friday, July 14 |
| » Lost to Padres (44-45), 9-5 | Wrigley Field (22-16) | 43-41 | Lost 2 |
| » W: Eric Rasmussen (8-7) L: Dave Roberts (4-4) S: Rollie Fingers (20) | Second | 5 out |
| Saturday, July 15 |
| » Defeated Padres (44-46), 3-1 | Wrigley Field (23-16) | 44-41 | |
| » W: Bruce Sutter (6-3) L: John D'Acquisto (1-3) | Second | 4 out |
| Sunday, July 16 |
| » Defeated Dodgers (51-39), 3-2 | Wrigley Field (24-16) | 45-41 | Won 2 |
| » W: Mike Krukow (4-0) L: Rick Rhoden (7-5) S: Bruce Sutter (15) | Second | 4½ out |
| » Lost to Dodgers (52-39), 5-3 | Wrigley Field (24-17) | 45-42 | |
| » W: Burt Hooton (9-7) L: Ray Burris (5-7) S: Lance Rautzhan (3) | Second | 4½ out |
| Monday, July 17 |
| » Lost to Dodgers (53-39), 4-3 | Wrigley Field (24-18) | 45-43 | Lost 2 |
| » W: Terry Forster (2-2) L: Rick Reuschel (8-7) S: Bob Welch (3) | Second | 4½ out |
| Tuesday, July 18 |
| » Defeated Giants (56-37), 7-6 | Wrigley Field (25-18) | 46-43 | |
| » W: Bruce Sutter (7-3) L: Charlie Williams (1-2) | Second | 3½ out |
| Wednesday, July 19 |
| » Lost to Giants (57-37), 7-4 | Wrigley Field (25-19) | 46-44 | |
| » W: Vida Blue (13-4) L: Ray Burris (5-8) S: Gary Lavelle (11) | Second | 3 out |
| » Defeated Giants (57-38), 7-5 | Wrigley Field (26-19) | 47-44 | |
| » W: Donnie Moore (5-2) L: Jim Barr (4-8) S: Bruce Sutter (16) | Second | 3 out |
| Thursday, July 20 |
| » Lost to Giants (58-38), 9-8 | Wrigley Field (26-20) | 47-45 | |
| » W: Gary Lavelle (9-7) L: Donnie Moore (5-3) S: Randy Moffitt (7) | Second | 4 out |
| Friday, July 21 |
| » Defeated Padres (46-51), 5-4 | San Diego/Jack Murphy Stadium (3-1) | 48-45 | |
| » W: Rick Reuschel (9-7) L: Bob Shirley (5-11) S: Bruce Sutter (17) | Second | 4½ out |
| Saturday, July 22 |
| » Lost to Padres (47-51), 4-2 | San Diego/Jack Murphy Stadium (3-2) | 48-46 | |
| » W: John D'Acquisto (2-3) L: Ray Burris (5-9) | Second | 5½ out |
| Sunday, July 23 |
| » Defeated Padres (47-52), 4-3 | San Diego/Jack Murphy Stadium (4-2) | 49-46 | |
| » W: Dennis Lamp (3-10) L: Randy Jones (7-9) | Second | 5½ out |
| Monday, July 24 |
| » Lost to Dodgers (57-42), 3-2 | Dodger Stadium (2-2) | 49-47 | |
| » W: Terry Forster (3-3) L: Donnie Moore (5-4) | Second | 5½ out |
| Tuesday, July 25 |
| » Lost to Dodgers (58-42), 3-1 | Dodger Stadium (2-3) | 49-48 | Lost 2 |
| » W: Rick Rhoden (8-5) L: Rick Reuschel (9-8) S: Tommy John (1) | Second | 5½ out |
| Wednesday, July 26 |
| » Lost to Dodgers (59-42), 8-2 | Dodger Stadium (2-4) | 49-49 | Lost 3 |
| » W: Burt Hooton (11-7) L: Dave Roberts (4-5) | Second | 5½ out |
| Friday, July 28 |
| » Defeated Giants (61-41), 1-0 | Candlestick Park (1-2) | 50-49 | |
| » W: Dennis Lamp (4-10) L: Bob Knepper (11-7) | Second | 5 out |
| Saturday, July 29 |
| » Defeated Giants (61-42), 5-3 | Candlestick Park (2-2) | 51-49 | Won 2 |
| » W: Willie Hernandez (6-2) L: Gary Lavelle (9-8) S: Ray Burris (1) | Second | 4 out |
| Sunday, July 30 |
| » Lost to Giants (62-42), 4-2 | Candlestick Park (2-3) | 51-50 | |
| » W: Jim Barr (6-8) L: Rick Reuschel (9-9) S: Randy Moffitt (8) | Second | 4½ out |
| » Lost to Giants (63-42), 1-0 | Candlestick Park (2-4) | 51-51 | Lost 2 |
| » W: Vida Blue (15-4) L: Dave Roberts (4-6) | Second | 4½ out |
| Tuesday, August 1 |
| » Defeated Cardinals (40-65), 4-2 | Wrigley Field (27-20) | 52-51 | |
| » W: Dennis Lamp (5-10) L: Silvio Martinez (5-5) S: Bruce Sutter (18) | Second | 4 out |
| Wednesday, August 2 |
| » Defeated Cardinals (40-66), 3-2 | Wrigley Field (28-20) | 53-51 | Won 2 |
| » W: Mike Krukow (5-0) L: Aurelio Lopez (0-1) S: Bruce Sutter (19) | Second | 4 out |
| Thursday, August 3 |
| » Defeated Cardinals (40-67), 3-2 | Wrigley Field (29-20) | 54-51 | Won 3 |
| » W: Donnie Moore (6-4) L: Pete Vuckovich (8-9) | Second | 3½ out |
| Friday, August 4 |
| » Defeated Expos (51-59), 6-4 | Wrigley Field (30-20) | 55-51 | Won 4 |
| » W: Rick Reuschel (10-9) L: Mike Garman (2-5) S: Bruce Sutter (20) | Second | 3 out |
| Saturday, August 5 |
| » Lost to Expos (52-59), 7-4 | Wrigley Field (30-21) | 55-52 | |
| » W: Ross Grimsley (13-8) L: Dave Roberts (4-7) S: Stan Bahnsen (6) | Second | 3½ out |
| Sunday, August 6 |
| » Lost to Expos (53-59), 2-1 | Wrigley Field (30-22) | 55-53 | Lost 2 |
| » W: Steve Rogers (13-7) L: Dennis Lamp (5-11) S: Darold Knowles (5) | Second | 4½ out |
| » Defeated Expos (53-60), 4-3 | Wrigley Field (31-22) | 56-53 | |
| » W: Lynn McGlothen (3-1) L: Mike Garman (2-6) S: Bruce Sutter (21) | Second | 4½ out |
| » Major-league debuts: Scott Sanderson (Expos) |
| Monday, August 7 |
| » Defeated Pirates (50-57), 5-4 | Wrigley Field (32-22) | 57-53 | Won 2 |
| » W: Donnie Moore (7-4) L: Jerry Reuss (0-2) S: Bruce Sutter (22) | Second | 3½ out |
| Tuesday, August 8 |
| » Lost to Pirates (51-57), 9-5 | Wrigley Field (32-23) | 57-54 | |
| » W: Don Robinson (7-5) L: Rick Reuschel (10-10) | Second | 3 out |
| Wednesday, August 9 |
| » Defeated Pirates (51-58), 5-4 | Wrigley Field (33-23) | 58-54 | |
| » W: Dave Roberts (5-7) L: Ed Whitson (3-5) | Second | 3 out |
| Friday, August 11 |
| » Lost to Expos (55-61), 1-0 | Stade Olympique (0-4) | 58-55 | |
| » W: Ross Grimsley (14-8) L: Dennis Lamp (5-12) | Second | 4½ out |
| Saturday, August 12 |
| » Lost to Expos (56-61), 4-3 | Stade Olympique (0-5) | 58-56 | Lost 2 |
| » W: Stan Bahnsen (1-4) L: Donnie Moore (7-5) | Second | 5½ out |
| Sunday, August 13 |
| » Defeated Expos (56-62), 2-1 | Stade Olympique (1-5) | 59-56 | |
| » W: Rick Reuschel (11-10) L: Scott Sanderson (0-1) | Second | 4½ out |
| Monday, August 14 |
| » Defeated Braves (54-63), 13-7 | Wrigley Field (34-23) | 60-56 | Won 2 |
| » W: Lynn McGlothen (4-1) L: Mickey Mahler (4-6) | Second | 4 out |
| Tuesday, August 15 |
| » Defeated Braves (54-64), 12-8 | Wrigley Field (35-23) | 61-56 | Won 3 |
| » W: Donnie Moore (8-5) L: Rick Camp (2-3) | Second | 3 out |
| Wednesday, August 16 |
| » Lost to Braves (55-64), 9-0 | Wrigley Field (35-24) | 61-57 | |
| » W: Phil Niekro (15-12) L: Mike Krukow (5-1) | Second | 3 out |
| Thursday, August 17 |
| » Defeated Reds (68-53), 2-0 | Wrigley Field (36-24) | 62-57 | |
| » W: Rick Reuschel (12-10) L: Tom Seaver (11-12) | Second | 2 out |
| Friday, August 18 |
| » Lost to Reds (69-53), 8-3 | Wrigley Field (36-25) | 62-58 | |
| » W: Pedro Borbon (6-2) L: Dave Roberts (5-8) S: Tom Hume (1) | Second | 2 out |
| Saturday, August 19 |
| » Lost to Reds (70-53), 9-7 | Wrigley Field (36-26) | 62-59 | Lost 2 |
| » W: Tom Hume (6-11) L: Bruce Sutter (7-4) | Second | 3 out |
| Sunday, August 20 |
| » Defeated Reds (70-54), 2-1 | Wrigley Field (37-26) | 63-59 | |
| » W: Willie Hernandez (7-2) L: Mike LaCoss (3-3) | Second | 3 out |
| Monday, August 21 |
| » Lost to Astros (57-68), 8-3 | Astrodome (1-3) | 63-60 | |
| » W: J.R. Richard (13-11) L: Rick Reuschel (12-11) | Second | 3 out |
| Tuesday, August 22 |
| » Lost to Astros (58-68), 2-1 | Astrodome (1-4) | 63-61 | Lost 2 |
| » W: Mark Lemongello (9-11) L: Mike Krukow (5-2) | Second | 4 out |
| Wednesday, August 23 |
| » Lost to Astros (59-68), 3-0 | Astrodome (1-5) | 63-62 | Lost 3 |
| » W: Ken Forsch (7-4) L: Dennis Lamp (5-13) S: Joe Sambito (9) | Second | 4 out |
| Friday, August 25 |
| » Defeated Reds (71-57), 5-2 | Riverfront Stadium (2-2) | 64-62 | |
| » W: Rick Reuschel (13-11) L: Mike LaCoss (3-4) | Second | 2½ out |
| Saturday, August 26 |
| » Defeated Reds (71-58), 8-6 | Riverfront Stadium (3-2) | 65-62 | Won 2 |
| » W: Dave Roberts (6-8) L: Doug Bair (6-5) S: Bruce Sutter (23) | Second | 2½ out |
| Sunday, August 27 |
| » Defeated Reds (71-59), 7-1 | Riverfront Stadium (4-2) | 66-62 | Won 3 |
| » W: Mike Krukow (6-2) L: Tom Seaver (11-13) | Second | 2½ out |
| Monday, August 28 |
| » Lost to Braves (57-73), 4-3 | Atlanta-Fulton County Stadium (2-2) | 66-63 | |
| » W: Phil Niekro (16-14) L: Donnie Moore (8-6) S: Gene Garber (20) | Second | 3½ out |
| Tuesday, August 29 |
| » Lost to Braves (58-73), 4-3 | Atlanta-Fulton County Stadium (2-3) | 66-64 | Lost 2 |
| » W: Eddie Solomon (4-4) L: Lynn McGlothen (4-2) S: Gene Garber (21) | Second | 4½ out |
| Wednesday, August 30 |
| » Lost to Braves (59-73), 6-2 | Atlanta-Fulton County Stadium (2-4) | 66-65 | Lost 3 |
| » W: Larry McWilliams (7-0) L: Ray Burris (5-10) | Third | 5½ out |
| Future Cub Todd Wellemeyer is born in Louisville, KY. |
| Friday, September 1 |
| » Defeated Astros (62-71), 14-11 | Wrigley Field (38-26) | 67-65 | |
| » W: Willie Hernandez (8-2) L: Joe Sambito (4-7) S: Bruce Sutter (24) | Third | 4½ out |
| Saturday, September 2 |
| » Lost to Astros (63-71), 8-5 | Wrigley Field (38-27) | 67-66 | |
| » W: Joaquin Andujar (5-4) L: Bruce Sutter (7-5) S: Joe Sambito (10) | Third | 5½ out |
| Sunday, September 3 |
| » Defeated Astros (63-72), 3-2 | Wrigley Field (39-27) | 68-66 | |
| » W: Dennis Lamp (6-13) L: Ken Forsch (8-5) S: Willie Hernandez (2) | Third | 3½ out |
| » Defeated Astros (63-73), 4-2 | Wrigley Field (40-27) | 69-66 | Won 2 |
| » W: Donnie Moore (9-6) L: Vern Ruhle (2-2) S: Willie Hernandez (3) | Third | 3½ out |
| » Major-league debuts: Scot Thompson (Cubs) |
| Monday, September 4 |
| » Lost to Expos (64-73), 5-3 | Wrigley Field (40-28) | 69-67 | |
| » W: Dan Schatzeder (7-4) L: Ray Burris (5-11) S: Darold Knowles (6) | Third | 4½ out |
| » Lost to Expos (65-73), 6-5 | Wrigley Field (40-29) | 69-68 | Lost 2 |
| » W: Mike Garman (4-6) L: Bruce Sutter (7-6) S: Bill Atkinson (3) | Third | 4½ out |
| Tuesday, September 5 |
| » Lost to Expos (66-73), 10-8 | Wrigley Field (40-30) | 69-69 | Lost 3 |
| » W: Wayne Twitchell (4-12) L: Bruce Sutter (7-7) S: Mike Garman (11) | Third | 5 out |
| Wednesday, September 6 |
| » Lost to Phillies (74-63), 8-1 | Wrigley Field (40-31) | 69-70 | Lost 4 |
| » W: Steve Carlton (13-12) L: Rick Reuschel (13-12) | Third | 6 out |
| Thursday, September 7 |
| » Lost to Phillies (75-63), 5-3 | Wrigley Field (40-32) | 69-71 | Lost 5 |
| » W: Warren Brusstar (5-3) L: Donnie Moore (9-7) S: Ron Reed (12) | Third | 7 out |
| Friday, September 8 |
| » Defeated Expos (67-75), 4-2 | Stade Olympique (2-5) | 70-71 | |
| » W: Bruce Sutter (8-7) L: Mike Garman (4-7) | Third | 7½ out |
| Saturday, September 9 |
| » Defeated Expos (67-76), 6-3 | Stade Olympique (3-5) | 71-71 | Won 2 |
| » W: Mike Krukow (7-2) L: Dan Schatzeder (7-5) S: Bruce Sutter (25) | Third | 7½ out |
| » Major-league debuts: David Palmer (Expos) |
| Sunday, September 10 |
| » Defeated Expos (67-77), 6-3 | Stade Olympique (4-5) | 72-71 | Won 3 |
| » W: Rick Reuschel (14-12) L: Woodie Fryman (7-10) | Third | 6½ out |
| Monday, September 11 |
| » Defeated Mets (59-86), 9-4 | Shea Stadium (5-3) | 73-71 | Won 4 |
| » W: Dennis Lamp (7-13) L: Mike Bruhert (3-9) | Third | 6½ out |
| » Major-league debuts: Alex Trevino (Mets) |
| Wednesday, September 13 |
| » Lost to Phillies (80-65), 6-2 | Veteran's Stadium (1-7) | 73-72 | |
| » W: Dick Ruthven (14-10) L: Ray Burris (5-12) | Third | 7 out |
| Thursday, September 14 |
| » Lost to Phillies (81-65), 11-5 | Veteran's Stadium (1-8) | 73-73 | Lost 2 |
| » W: Warren Brusstar (6-3) L: Rick Reuschel (14-13) S: Ron Reed (13) | Third | 8 out |
| Friday, September 15 |
| » Lost to Cardinals (63-86), 6-2 | Wrigley Field (40-33) | 73-74 | Lost 3 |
| » W: Mark Littell (3-8) L: Bruce Sutter (8-8) | Third | 8 out |
| Saturday, September 16 |
| » Lost to Cardinals (64-86), 4-1 | Wrigley Field (40-34) | 73-75 | Lost 4 |
| » W: John Denny (12-11) L: Dennis Lamp (7-14) S: Mark Littell (11) | Third | 9 out |
| Sunday, September 17 |
| » Defeated Cardinals (64-87), 4-2 | Wrigley Field (41-34) | 74-75 | |
| » W: Ray Burris (6-12) L: Pete Vuckovich (12-12) | Third |