| 2004-04-05 | vs SFN | 1 | L 4-5 | - | | 43,351 | Roy Oswalt | Kirk Rueter | Felix Rodriguez | Octavio Dotel | Matt Herges | 4 | 5 | -1 |
| 2004-04-06 | vs SFN | 2 | L 5-7 | - | | 40,660 | Andy Pettitte | Brett Tomko | David Aardsma | Andy Pettitte | Matt Herges | 9 | 12 | -3 |
| 2004-04-07 | vs SFN | 3 | W 10-1 | - | | 42,863 | Roger Clemens | Jerome Williams | Roger Clemens | Jerome Williams | | 19 | 13 | 6 |
| 2004-04-09 | @ MIL | 4 | W 13-7 | - | | 44,405 | Wade Miller | Wes Obermueller | Wade Miller | Wes Obermueller | | 32 | 20 | 12 |
| 2004-04-10 | @ MIL | 5 | L 1-6 | - | | 18,337 | Tim Redding | Ben Sheets | Ben Sheets | Tim Redding | | 33 | 26 | 7 |
| 2004-04-11 | @ MIL | 6 | W 7-4 | - | | 11,262 | Roy Oswalt | Doug Davis | Roy Oswalt | Doug Davis | | 40 | 30 | 10 |
| 2004-04-12 | @ SLN | 7 | W 10-5 | - | | 26,654 | Jared Fernandez | Woody Williams | Ricky Stone | Mike Lincoln | | 50 | 35 | 15 |
| 2004-04-13 | @ SLN | 8 | W 5-3 | - | | 24,939 | Roger Clemens | Jeff Suppan | Roger Clemens | Jeff Suppan | Octavio Dotel | 55 | 38 | 17 |
| 2004-04-14 | @ SLN | 9 | W 11-1 | - | | 26,605 | Wade Miller | Chris Carpenter | Wade Miller | Chris Carpenter | | 66 | 39 | 27 |
| 2004-04-15 | vs MIL | 10 | L 2-6 | - | | 33,010 | Tim Redding | Ben Sheets | Ben Sheets | Tim Redding | | 68 | 45 | 23 |
| 2004-04-16 | vs MIL | 11 | W 2-0 | - | | 32,656 | Roy Oswalt | Doug Davis | Roy Oswalt | Doug Davis | | 70 | 45 | 25 |
| 2004-04-17 | vs MIL | 12 | W 14-5 | - | | 40,030 | Brandon Duckworth | Matt Kinney | Brandon Backe | Matt Kinney | | 84 | 50 | 34 |
| 2004-04-18 | vs MIL | 13 | W 6-1 | - | | 38,195 | Roger Clemens | Chris Capuano | Roger Clemens | Chris Capuano | | 90 | 51 | 39 |
| 2004-04-20 | vs SLN | 14 | L 3-5 | - | | 29,625 | Wade Miller | Jeff Suppan | Jeff Suppan | Wade Miller | Jason Isringhausen | 93 | 56 | 37 |
| 2004-04-21 | vs SLN | 15 | L 6-12 | - | | 27,354 | Tim Redding | Matt Morris | Matt Morris | Tim Redding | | 99 | 68 | 31 |
| 2004-04-22 | vs SLN | 16 | L 1-2 | - | | 33,706 | Roy Oswalt | Jason Marquis | Jason Isringhausen | Dan Miceli | Julian Tavarez | 100 | 70 | 30 |
| 2004-04-23 | @ COL | 17 | W 13-7 | - | | 23,719 | Brandon Duckworth | Jason Jennings | Brandon Duckworth | Jason Jennings | | 113 | 77 | 36 |
| 2004-04-24 | @ COL | 18 | W 8-5 | - | | 35,260 | Roger Clemens | Jeff Fassero | Roger Clemens | Jeff Fassero | Octavio Dotel | 121 | 82 | 39 |
| 2004-04-25 | @ COL | 19 | L 1-4 | - | | 30,912 | Wade Miller | Joe Kennedy | Joe Kennedy | Wade Miller | Shawn Chacon | 122 | 86 | 36 |
| 2004-04-28 | @ PIT | 20 | L 2-4 | - | | 9,813 | Roy Oswalt | Josh Fogg | Salomon Torres | Roy Oswalt | Jose Mesa | 124 | 90 | 34 |
| 2004-04-29 | @ PIT | 21 | W 2-0 | - | | 19,485 | Andy Pettitte | Kip Wells | Andy Pettitte | Kip Wells | Octavio Dotel | 126 | 90 | 36 |
| 2004-04-30 | vs CIN | 22 | W 6-1 | - | | 41,430 | Roger Clemens | Jose Acevedo | Roger Clemens | Jose Acevedo | | 132 | 91 | 41 |
| 2004-05-01 | vs CIN | 23 | W 10-4 | - | | 40,104 | Wade Miller | Aaron Harang | Wade Miller | Aaron Harang | | 142 | 95 | 47 |
| 2004-05-02 | vs CIN | 24 | W 6-5 | - | | 38,313 | Tim Redding | Cory Lidle | Dan Miceli | Todd Jones | Octavio Dotel | 148 | 100 | 48 |
| 2004-05-03 | vs CIN | 25 | L 5-7 | - | | 30,657 | Roy Oswalt | Paul Wilson | John Riedling | Brad Lidge | Danny Graves | 153 | 107 | 46 |
| 2004-05-04 | vs PIT | 26 | W 4-3 | - | | 31,083 | Andy Pettitte | Josh Fogg | Andy Pettitte | Josh Fogg | Brad Lidge | 157 | 110 | 47 |
| 2004-05-05 | vs PIT | 27 | W 6-2 | - | | 35,883 | Roger Clemens | Kip Wells | Roger Clemens | Kip Wells | | 163 | 112 | 51 |
| 2004-05-06 | vs PIT | 28 | W 5-2 | - | | 36,055 | Wade Miller | Kris Benson | Wade Miller | Kris Benson | | 168 | 114 | 54 |
| 2004-05-07 | @ ATL | 29 | W 5-3 | - | | 27,902 | Tim Redding | John Thomson | Tim Redding | John Thomson | Octavio Dotel | 173 | 117 | 56 |
| 2004-05-08 | @ ATL | 30 | L 4-5 | - | | 35,220 | Roy Oswalt | Horacio Ramirez | Antonio Alfonseca | Ricky Stone | | 177 | 122 | 55 |
| 2004-05-09 | @ ATL | 31 | W 2-1 | - | | 26,825 | Andy Pettitte | Russ Ortiz | Andy Pettitte | Russ Ortiz | Octavio Dotel | 179 | 123 | 56 |
| 2004-05-11 | vs FLO | 32 | W 6-1 | - | | 37,958 | Roger Clemens | Brad Penny | Roger Clemens | Brad Penny | | 185 | 124 | 61 |
| 2004-05-12 | vs FLO | 33 | L 2-5 | - | | 33,689 | Wade Miller | Dontrelle Willis | Dontrelle Willis | Wade Miller | | 187 | 129 | 58 |
| 2004-05-13 | vs FLO | 34 | L 2-3 | - | | 30,847 | Tim Redding | Carl Pavano | Matt Perisho | Octavio Dotel | Armando Benitez | 189 | 132 | 57 |
| 2004-05-14 | vs NYN | 35 | L 3-8 | - | | 35,849 | Roy Oswalt | Steve Trachsel | Steve Trachsel | Roy Oswalt | | 192 | 140 | 52 |
| 2004-05-15 | vs NYN | 36 | W 7-4 | - | | 42,581 | Andy Pettitte | James Baldwin | Andy Pettitte | James Baldwin | Octavio Dotel | 199 | 144 | 55 |
| 2004-05-16 | vs NYN | 37 | L 2-3 | - | | 43,247 | Roger Clemens | Matt Ginter | Dan Wheeler | Brandon Backe | | 201 | 147 | 54 |
| 2004-05-18 | @ FLO | 38 | W 9-2 | - | | 12,324 | Wade Miller | Dontrelle Willis | Wade Miller | Dontrelle Willis | | 210 | 149 | 61 |
| 2004-05-19 | @ FLO | 39 | W 10-2 | - | | 12,122 | Tim Redding | Carl Pavano | Tim Redding | Carl Pavano | | 220 | 151 | 69 |
| 2004-05-20 | @ FLO | 40 | L 2-6 | - | | 13,165 | Roy Oswalt | Josh Beckett | Josh Beckett | Roy Oswalt | Armando Benitez | 222 | 157 | 65 |
| 2004-05-21 | @ CIN | 41 | L 4-7 | - | | 31,832 | Andy Pettitte | Todd Van Poppel | Ryan Wagner | Dan Miceli | Danny Graves | 226 | 164 | 62 |
| 2004-05-22 | @ CIN | 42 | L 7-8 | - | | 41,890 | Roger Clemens | Aaron Harang | Todd Jones | Brad Lidge | Danny Graves | 233 | 172 | 61 |
| 2004-05-23 | @ CIN | 43 | L 0-7 | - | | 29,693 | Wade Miller | Cory Lidle | Cory Lidle | Wade Miller | | 233 | 179 | 54 |
| 2004-05-24 | @ CIN | 44 | L 5-7 | - | | 28,008 | Tim Redding | Jose Acevedo | John Riedling | Brad Lidge | Danny Graves | 238 | 186 | 52 |
| 2004-05-25 | vs CHN | 45 | W 5-0 | - | | 40,154 | Roy Oswalt | Carlos Zambrano | Roy Oswalt | Carlos Zambrano | | 243 | 186 | 57 |
| 2004-05-26 | vs CHN | 46 | W 7-3 | - | | 40,977 | Andy Pettitte | Greg Maddux | Brad Lidge | Greg Maddux | | 250 | 189 | 61 |
| 2004-05-28 | vs SLN | 47 | L 1-2 | - | | 41,399 | Roger Clemens | Chris Carpenter | Jason Isringhausen | Octavio Dotel | | 251 | 191 | 60 |
| 2004-05-29 | vs SLN | 48 | L 3-10 | - | | 41,141 | Wade Miller | Woody Williams | Woody Williams | Wade Miller | | 254 | 201 | 53 |
| 2004-05-30 | vs SLN | 49 | W 7-1 | - | | 41,117 | Tim Redding | Matt Morris | Tim Redding | Matt Morris | | 261 | 202 | 59 |
| 2004-05-31 | @ CHN | 50 | L 1-3 | - | | 39,380 | Roy Oswalt | Greg Maddux | Greg Maddux | Roy Oswalt | Joe Borowski | 262 | 205 | 57 |
| 2004-06-01 | @ CHN | 51 | W 5-3 | - | | 38,667 | Brandon Duckworth | Glendon Rusch | Dan Miceli | Kyle Farnsworth | Octavio Dotel | 267 | 208 | 59 |
| 2004-06-02 | @ CHN | 52 | W 5-1 | - | | 38,346 | Roger Clemens | Matt Clement | Roger Clemens | Matt Clement | | 272 | 209 | 63 |
| 2004-06-04 | @ SLN | 53 | L 3-5 | - | | 47,373 | Wade Miller | Matt Morris | Matt Morris | Wade Miller | Jason Isringhausen | 275 | 214 | 61 |
| 2004-06-05 | @ SLN | 54 | L 4-10 | - | | 46,003 | Tim Redding | Jason Marquis | Jason Marquis | Tim Redding | | 279 | 224 | 55 |
| 2004-06-06 | @ SLN | 55 | W 3-2 | - | | 40,476 | Roy Oswalt | Jeff Suppan | Roy Oswalt | Jeff Suppan | Octavio Dotel | 282 | 226 | 56 |
| 2004-06-07 | @ SEA | 56 | L 0-5 | - | | 28,556 | Brandon Duckworth | Clint Nageotte | Clint Nageotte | Brandon Duckworth | Julio Mateo | 282 | 231 | 51 |
| 2004-06-08 | @ SEA | 57 | W 1-0 | - | | 34,238 | Roger Clemens | Joel Pineiro | Roger Clemens | Joel Pineiro | Octavio Dotel | 283 | 231 | 52 |
| 2004-06-09 | @ SEA | 58 | W 3-0 | - | | 33,214 | Wade Miller | Freddy Garcia | Wade Miller | Freddy Garcia | Octavio Dotel | 286 | 231 | 55 |
| 2004-06-11 | @ MIL | 59 | L 3-9 | - | | 26,141 | Tim Redding | Doug Davis | Doug Davis | Tim Redding | | 289 | 240 | 49 |
| 2004-06-12 | @ MIL | 60 | L 4-7 | - | | 40,223 | Roy Oswalt | Chris Capuano | Chris Capuano | Roy Oswalt | Danny Kolb | 293 | 247 | 46 |
| 2004-06-13 | @ MIL | 61 | W 5-4 | - | | 23,007 | Peter Munro | Ben Sheets | Dan Miceli | Ben Sheets | Octavio Dotel | 298 | 251 | 47 |
| 2004-06-14 | vs CHN | 62 | L 2-7 | - | | 43,067 | Roger Clemens | Mark Prior | Mark Prior | Roger Clemens | Jimmy Anderson | 300 | 258 | 42 |
| 2004-06-15 | vs CHN | 63 | L 2-4 | - | | 38,007 | Wade Miller | Carlos Zambrano | Kyle Farnsworth | Octavio Dotel | LaTroy Hawkins | 302 | 262 | 40 |
| 2004-06-16 | vs CHN | 64 | L 1-4 | - | | 36,225 | Tim Redding | Greg Maddux | Greg Maddux | Tim Redding | LaTroy Hawkins | 303 | 266 | 37 |
| 2004-06-17 | vs CHN | 65 | L 4-5 | - | | 41,397 | Roy Oswalt | Glendon Rusch | Glendon Rusch | Roy Oswalt | LaTroy Hawkins | 307 | 271 | 36 |
| 2004-06-18 | vs ANA | 66 | W 5-0 | - | | 38,328 | Peter Munro | Kelvim Escobar | Peter Munro | Kelvim Escobar | | 312 | 271 | 41 |
| 2004-06-19 | vs ANA | 67 | L 4-6 | - | | 42,449 | Roger Clemens | Ramon Ortiz | Ramon Ortiz | Roger Clemens | Francisco Rodriguez | 316 | 277 | 39 |
| 2004-06-20 | vs ANA | 68 | W 3-1 | - | | 41,590 | Wade Miller | Jarrod Washburn | Wade Miller | Matt Hensley | Octavio Dotel | 319 | 278 | 41 |
| 2004-06-21 | vs PIT | 69 | W 7-5 | - | | 33,443 | Tim Redding | Josh Fogg | Kirk Bullinger | Josh Fogg | Octavio Dotel | 326 | 283 | 43 |
| 2004-06-22 | vs PIT | 70 | W 5-4 | - | | 31,819 | Roy Oswalt | Kris Benson | Roy Oswalt | Kris Benson | Brad Lidge | 331 | 287 | 44 |
| 2004-06-23 | vs PIT | 71 | L 2-7 | - | | 34,242 | Peter Munro | Ryan Vogelsong | Ryan Vogelsong | Peter Munro | | 333 | 294 | 39 |
| 2004-06-24 | vs PIT | 72 | W 3-2 | - | | 39,851 | Roger Clemens | Sean Burnett | Roger Clemens | Sean Burnett | Brad Lidge | 336 | 296 | 40 |
| 2004-06-25 | @ TEX | 73 | L 1-3 | - | | 46,088 | Wade Miller | Kenny Rogers | Kenny Rogers | Wade Miller | | 337 | 299 | 38 |
| 2004-06-26 | @ TEX | 74 | L 7-8 | - | | 40,131 | Tim Redding | John Wasdin | Carlos Almanzar | Dan Miceli | Francisco Cordero | 344 | 307 | 37 |
| 2004-06-27 | @ TEX | 75 | W 1-0 | - | | 43,328 | Roy Oswalt | Ryan Drese | Roy Oswalt | Ryan Drese | Brad Lidge | 345 | 307 | 38 |
| 2004-06-29 | @ CHN | 76 | L 5-7 | - | | 40,008 | Andy Pettitte | Glendon Rusch | Francis Beltran | David Weathers | LaTroy Hawkins | 350 | 314 | 36 |
| 2004-06-30 | @ CHN | 77 | W 3-2 | - | | 39,326 | Roger Clemens | Matt Clement | Brad Lidge | LaTroy Hawkins | | 353 | 316 | 37 |
| 2004-07-01 | @ CHN | 78 | L 4-5 | - | | 39,116 | Peter Munro | Mark Prior | Jon Leicester | Brad Lidge | | 357 | 321 | 36 |
| 2004-07-02 | vs TEX | 79 | W 7-5 | - | | 41,897 | Roy Oswalt | Ryan Drese | Roy Oswalt | Carlos Almanzar | Brad Lidge | 364 | 326 | 38 |
| 2004-07-03 | vs TEX | 80 | W 10-8 | - | | 42,889 | Jeremy Griffiths | Ricardo Rodriguez | David Weathers | Doug Brocail | Dan Miceli | 374 | 334 | 40 |
| 2004-07-04 | vs TEX | 81 | L 3-18 | - | | 41,147 | Andy Pettitte | Joaquin Benoit | Joaquin Benoit | Andy Pettitte | | 377 | 352 | 25 |
| 2004-07-05 | @ SDN | 82 | L 1-2 | - | | 39,653 | Roger Clemens | Brian Lawrence | Brian Lawrence | Dan Miceli | Trevor Hoffman | 378 | 354 | 24 |
| 2004-07-06 | @ SDN | 83 | L 3-5 | - | | 31,540 | Peter Munro | Ismael Valdez | Ismael Valdez | Peter Munro | Trevor Hoffman | 381 | 359 | 22 |
| 2004-07-07 | @ SDN | 84 | W 5-1 | - | | 31,402 | Roy Oswalt | Jake Peavy | Roy Oswalt | Jake Peavy | Brad Lidge | 386 | 360 | 26 |
| 2004-07-08 | @ LAN | 85 | L 2-7 | - | | 33,324 | Brandon Duckworth | Edwin Jackson | Edwin Jackson | Brandon Duckworth | Tom Martin | 388 | 367 | 21 |
| 2004-07-09 | @ LAN | 86 | W 3-2 | - | | 52,783 | Andy Pettitte | Jeff Weaver | Andy Pettitte | Jeff Weaver | Brad Lidge | 391 | 369 | 22 |
| 2004-07-10 | @ LAN | 87 | L 1-3 | - | | 46,321 | Roger Clemens | Wilson Alvarez | Wilson Alvarez | Roger Clemens | Eric Gagne | 392 | 372 | 20 |
| 2004-07-11 | @ LAN | 88 | L 4-7 | - | | 40,484 | Roy Oswalt | Jose Lima | Jose Lima | Roy Oswalt | | 396 | 379 | 17 |
| 2004-07-16 | vs SDN | 89 | L 1-5 | - | | 39,106 | Andy Pettitte | Jake Peavy | Jake Peavy | Andy Pettitte | | 397 | 384 | 13 |
| 2004-07-17 | vs SDN | 90 | L 4-7 | - | | 39,714 | Roy Oswalt | David Wells | David Wells | Roy Oswalt | Trevor Hoffman | 401 | 391 | 10 |
| 2004-07-18 | vs SDN | 91 | W 5-3 | - | | 38,094 | Roger Clemens | Brian Lawrence | Roger Clemens | Brian Lawrence | Brad Lidge | 406 | 394 | 12 |
| 2004-07-19 | vs LAN | 92 | L 6-7 | - | | 35,155 | Brandon Duckworth | Wilson Alvarez | Giovanni Carrara | Dan Miceli | Eric Gagne | 412 | 401 | 11 |
| 2004-07-20 | vs LAN | 93 | L 5-7 | - | | 34,154 | Peter Munro | Jeff Weaver | Jeff Weaver | David Weathers | Eric Gagne | 417 | 408 | 9 |
| 2004-07-21 | @ ARI | 94 | W 5-2 | - | | 26,907 | Andy Pettitte | Brandon Webb | Andy Pettitte | Brandon Webb | Brad Lidge | 422 | 410 | 12 |
| 2004-07-22 | @ ARI | 95 | W 10-3 | - | | 26,003 | Roy Oswalt | Edgar Gonzalez | Roy Oswalt | Edgar Gonzalez | | 432 | 413 | 19 |
| 2004-07-23 | vs MIL | 96 | L 6-7 | - | | 36,732 | Roger Clemens | Chris Capuano | Luis Vizcaino | Brad Lidge | Danny Kolb | 438 | 420 | 18 |
| 2004-07-24 | vs MIL | 97 | W 6-3 | - | | 40,334 | Tim Redding | Ben Hendrickson | Tim Redding | Ben Hendrickson | Brad Lidge | 444 | 423 | 21 |
| 2004-07-25 | vs MIL | 98 | W 9-1 | - | | 32,971 | Peter Munro | Doug Davis | Peter Munro | Doug Davis | | 453 | 424 | 29 |
| 2004-07-26 | vs ARI | 99 | L 1-4 | - | | 36,046 | Andy Pettitte | Brandon Webb | Brandon Webb | Andy Pettitte | Greg Aquino | 454 | 428 | 26 |
| 2004-07-27 | vs ARI | 100 | W 10-3 | - | | 32,095 | Roy Oswalt | Edgar Gonzalez | Roy Oswalt | Edgar Gonzalez | | 464 | 431 | 33 |
| 2004-07-28 | vs ARI | 101 | W 6-1 | - | | 35,191 | Roger Clemens | Casey Fossum | Roger Clemens | Casey Fossum | | 470 | 432 | 38 |
| 2004-07-29 | vs ARI | 102 | L 4-6 | - | | 39,758 | Tim Redding | Lance Cormier | Lance Cormier | Tim Redding | Greg Aquino | 474 | 438 | 36 |
| 2004-07-30 | @ CIN | 103 | L 2-3 | - | | 32,691 | Peter Munro | Aaron Harang | Josh Hancock | Chad Harville | | 476 | 441 | 35 |
| 2004-07-31 | @ CIN | 104 | W 8-0 | - | | 36,415 | Darren Oliver | Brandon Claussen | Darren Oliver | Brandon Claussen | | 484 | 441 | 43 |
| 2004-08-01 | @ CIN | 105 | W 7-5 | - | | 34,002 | Roy Oswalt | Paul Wilson | Roy Oswalt | John Riedling | Brad Lidge | 491 | 446 | 45 |
| 2004-08-03 | vs ATL | 106 | W 3-2 | - | | 40,709 | Roger Clemens | Russ Ortiz | Dan Miceli | Chris Reitsma | Brad Lidge | 494 | 448 | 46 |
| 2004-08-04 | vs ATL | 107 | L 4-5 | - | | 18,196 | Peter Munro | John Thomson | John Thomson | Peter Munro | John Smoltz | 498 | 453 | 45 |
| 2004-08-05 | vs ATL | 108 | L 5-6 | - | | 37,015 | Darren Oliver | Mike Hampton | Juan Cruz | Dan Miceli | John Smoltz | 503 | 459 | 44 |
| 2004-08-06 | vs MON | 109 | W 4-0 | - | | 35,921 | Roy Oswalt | Rocky Biddle | Roy Oswalt | Rocky Biddle | | 507 | 459 | 48 |
| 2004-08-07 | vs MON | 110 | L 3-8 | - | | 39,840 | Andy Pettitte | Jon Rauch | Jon Rauch | David Weathers | | 510 | 467 | 43 |
| 2004-08-08 | vs MON | 111 | L 2-5 | - | | 38,407 | Roger Clemens | Sun-Woo Kim | T.J. Tucker | Roger Clemens | | 512 | 472 | 40 |
| 2004-08-10 | @ NYN | 112 | L 3-7 | - | | 28,472 | Peter Munro | Steve Trachsel | Steve Trachsel | Peter Munro | | 515 | 479 | 36 |
| 2004-08-11 | @ NYN | 113 | W 5-4 | - | | 32,060 | Roy Oswalt | Matt Ginter | Brad Lidge | Braden Looper | Kirk Bullinger | 520 | 483 | 37 |
| 2004-08-12 | @ NYN | 114 | L 1-2 | - | | 26,419 | Andy Pettitte | Victor Zambrano | Victor Zambrano | David Weathers | Braden Looper | 521 | 485 | 36 |
| 2004-08-13 | @ MON | 115 | L 5-6 | - | | 8,593 | Roger Clemens | Jon Rauch | Claudio Vargas | Chad Harville | | 526 | 491 | 35 |
| 2004-08-14 | @ MON | 116 | L 3-8 | - | | 11,929 | Carlos Hernandez | Tony Armas | T.J. Tucker | Carlos Hernandez | | 529 | 499 | 30 |
| 2004-08-15 | @ MON | 117 | W 5-4 | - | | 13,528 | Peter Munro | Livan Hernandez | Dan Miceli | Luis Ayala | Brad Lidge | 534 | 503 | 31 |
| 2004-08-17 | @ PHI | 118 | W 5-0 | - | | 43,716 | Roy Oswalt | Randy Wolf | Roy Oswalt | Randy Wolf | | 539 | 503 | 36 |
| 2004-08-18 | @ PHI | 119 | W 9-8 | - | | 43,895 | Roger Clemens | Cory Lidle | Chad Harville | Todd Jones | Brad Lidge | 548 | 511 | 37 |
| 2004-08-19 | @ PHI | 120 | W 12-10 | - | | 43,543 | Carlos Hernandez | Brett Myers | Chad Qualls | Roberto Hernandez | Brad Lidge | 560 | 521 | 39 |
| 2004-08-20 | vs CHN | 121 | L 2-9 | - | | 41,071 | Peter Munro | Glendon Rusch | Glendon Rusch | Peter Munro | | 562 | 530 | 32 |
| 2004-08-21 | vs CHN | 122 | W 4-3 | - | | 42,451 | Brandon Backe | Mark Prior | Brad Lidge | LaTroy Hawkins | | 566 | 533 | 33 |
| 2004-08-22 | vs CHN | 123 | L 6-11 | - | | 41,186 | Roy Oswalt | Kerry Wood | Jon Leicester | Roy Oswalt | | 572 | 544 | 28 |
| 2004-08-23 | vs PHI | 124 | W 8-4 | - | | 36,398 | Roger Clemens | Cory Lidle | Roger Clemens | Cory Lidle | | 580 | 548 | 32 |
| 2004-08-24 | vs PHI | 125 | W 4-2 | - | | 37,127 | Carlos Hernandez | Brett Myers | Roy Oswalt | Todd Jones | Brad Lidge | 584 | 550 | 34 |
| 2004-08-25 | vs PHI | 126 | W 7-4 | - | | 37,217 | Peter Munro | Eric Milton | Chad Qualls | Felix Rodriguez | Brad Lidge | 591 | 554 | 37 |
| 2004-08-26 | @ CHN | 127 | L 3-8 | - | | 38,216 | Brandon Backe | Mark Prior | Mark Prior | Brandon Backe | | 594 | 562 | 32 |
| 2004-08-27 | @ CHN | 128 | W 15-7 | - | | 39,038 | Roy Oswalt | Kerry Wood | Roy Oswalt | Kerry Wood | | 609 | 569 | 40 |
| 2004-08-28 | @ CHN | 129 | W 7-6 | - | | 39,081 | Roger Clemens | Carlos Zambrano | Roger Clemens | Carlos Zambrano | Brad Lidge | 616 | 575 | 41 |
| 2004-08-29 | @ CHN | 130 | W 10-3 | - | | 39,041 | Carlos Hernandez | Matt Clement | Carlos Hernandez | Matt Clement | | 626 | 578 | 48 |
| 2004-08-30 | @ CIN | 131 | W 11-3 | - | | 19,320 | Peter Munro | Luke Hudson | Peter Munro | Phil Norton | | 637 | 581 | 56 |
| 2004-08-31 | @ CIN | 132 | W 8-0 | - | | 19,586 | Brandon Backe | Aaron Harang | Brandon Backe | Aaron Harang | | 645 | 581 | 64 |
| 2004-09-01 | @ CIN | 133 | W 9-3 | - | | 17,270 | Roy Oswalt | Paul Wilson | Roy Oswalt | Paul Wilson | | 654 | 584 | 70 |
| 2004-09-03 | vs PIT | 134 | W 8-6 | - | | 40,992 | Roger Clemens | Oliver Perez | Roger Clemens | Oliver Perez | Brad Lidge | 662 | 590 | 72 |
| 2004-09-04 | vs PIT | 135 | W 6-5 | - | | 38,605 | Carlos Hernandez | Josh Fogg | Chad Qualls | Nelson Figueroa | Brad Lidge | 668 | 595 | 73 |
| 2004-09-05 | vs PIT | 136 | W 10-5 | - | | 40,569 | Peter Munro | Kip Wells | Peter Munro | John Van Benschoten | | 678 | 600 | 78 |
| 2004-09-06 | vs CIN | 137 | W 11-5 | - | | 40,581 | Brandon Backe | Aaron Harang | Brandon Backe | Aaron Harang | | 689 | 605 | 84 |
| 2004-09-07 | vs CIN | 138 | W 9-7 | - | | 36,921 | Roy Oswalt | Paul Wilson | Roy Oswalt | Paul Wilson | | 698 | 612 | 86 |
| 2004-09-08 | vs CIN | 139 | W 5-2 | - | | 35,445 | Roger Clemens | Jose Acevedo | Roger Clemens | Jose Acevedo | Brad Lidge | 703 | 614 | 89 |
| 2004-09-09 | @ PIT | 140 | L 1-3 | - | | 0 | Carlos Hernandez | Oliver Perez | Oliver Perez | Carlos Hernandez | Jose Mesa | 704 | 617 | 87 |
| 2004-09-09 | @ PIT | 141 | W 9-2 | - | | 10,495 | Tim Redding | Josh Fogg | Mike Gallo | Josh Fogg | | 713 | 619 | 94 |
| 2004-09-10 | @ PIT | 142 | L 1-6 | - | | 26,097 | Peter Munro | John Van Benschoten | John Van Benschoten | Peter Munro | | 714 | 625 | 89 |
| 2004-09-11 | @ PIT | 143 | L 2-5 | - | | 14,877 | Brandon Backe | Ryan Vogelsong | Ryan Vogelsong | Brandon Backe | Jose Mesa | 716 | 630 | 86 |
| 2004-09-12 | @ PIT | 144 | W 5-4 | - | | 11,521 | Roy Oswalt | David Williams | Brad Lidge | Jose Mesa | Chad Qualls | 721 | 634 | 87 |
| 2004-09-14 | @ SLN | 145 | W 7-5 | - | | 29,528 | Roger Clemens | Jeff Suppan | Roger Clemens | Jeff Suppan | Brad Lidge | 728 | 639 | 89 |
| 2004-09-15 | @ SLN | 146 | L 2-4 | - | | 32,891 | Carlos Hernandez | Matt Morris | Kiko Calero | Russ Springer | Jason Isringhausen | 730 | 643 | 87 |
| 2004-09-16 | @ SLN | 147 | W 8-3 | - | | 28,704 | Brandon Backe | Jason Marquis | Chad Harville | Jason Marquis | | 738 | 646 | 92 |
| 2004-09-17 | vs MIL | 148 | W 2-1 | - | | 38,839 | Roy Oswalt | Ben Sheets | Roy Oswalt | Ben Sheets | Brad Lidge | 740 | 647 | 93 |
| 2004-09-18 | vs MIL | 149 | W 4-3 | - | | 40,408 | Peter Munro | Gary Glover | Chad Harville | Gary Glover | Brad Lidge | 744 | 650 | 94 |
| 2004-09-19 | vs MIL | 150 | W 1-0 | - | | 35,678 | Roger Clemens | Doug Davis | Roger Clemens | Doug Davis | Brad Lidge | 745 | 650 | 95 |
| 2004-09-21 | @ SFN | 151 | L 2-9 | - | | 39,863 | Carlos Hernandez | Brett Tomko | Brett Tomko | Carlos Hernandez | | 747 | 659 | 88 |
| 2004-09-22 | @ SFN | 152 | L 1-5 | - | | 40,095 | Roy Oswalt | Noah Lowry | Noah Lowry | Roy Oswalt | | 748 | 664 | 84 |
| 2004-09-23 | @ SFN | 153 | W 7-3 | - | | 41,537 | Brandon Backe | Jason Schmidt | Dan Miceli | Dustin Hermanson | | 755 | 667 | 88 |
| 2004-09-24 | @ MIL | 154 | W 1-0 | - | | 34,890 | Roger Clemens | Doug Davis | Brad Lidge | Mike Adams | Dan Miceli | 756 | 667 | 89 |
| 2004-09-25 | @ MIL | 155 | L 0-8 | - | | 22,812 | Peter Munro | Wes Obermueller | Wes Obermueller | Peter Munro | | 756 | 675 | 81 |
| 2004-09-26 | @ MIL | 156 | W 11-7 | - | | 18,496 | Carlos Hernandez | Victor Santos | Tim Redding | Victor Santos | | 767 | 682 | 85 |
| 2004-09-27 | vs SLN | 157 | W 10-3 | - | | 37,651 | Roy Oswalt | Woody Williams | Roy Oswalt | Woody Williams | | 777 | 685 | 92 |
| 2004-09-28 | vs SLN | 158 | W 2-1 | - | | 36,230 | Brandon Backe | Dan Haren | Brandon Backe | Dan Haren | Brad Lidge | 779 | 686 | 93 |
| 2004-09-29 | vs SLN | 159 | W 6-4 | - | | 43,186 | Roger Clemens | Jeff Suppan | Chad Qualls | Jeff Suppan | Brad Lidge | 785 | 690 | 95 |
| 2004-10-01 | vs COL | 160 | W 4-2 | - | | 41,717 | Peter Munro | Joe Kennedy | Mike Gallo | Joe Kennedy | Brad Lidge | 789 | 692 | 97 |
| 2004-10-02 | vs COL | 161 | W 9-3 | - | | 43,279 | Roy Oswalt | Shawn Estes | Roy Oswalt | Shawn Estes | | 798 | 695 | 103 |
| 2004-10-03 | vs COL | 162 | W 5-3 | - | | 43,082 | Brandon Backe | Jamey Wright | Brandon Backe | Jamey Wright | Brad Lidge | 803 | 698 | 105 |