2003 Major League Baseball postseason
| Tournament details | |
|---|---|
| Dates | September 30 – October 25, 2003 |
| Teams | 8 |
| Final positions | |
| Champions | Florida Marlins
(2nd title) |
| Runners-up | New York Yankees |
| Tournament statistics | |
| Most HRs | Todd Walker (BOS) (5) |
| Most SBs | Alfonso Soriano (NYY) (5) |
| Most Ks (as pitcher) | Josh Beckett (FLA) (47) |
| Awards | |
| MVP | Josh Beckett (FLA) |
The 2003 Major League Baseball postseason was the playoff tournament of Major League Baseball for the 2003 season. The winners of the League Division Series would move on to the League Championship Series to determine the pennant winners that face each other in the World Series. This was the first edition of the postseason where home-field advantage in the World Series was awarded to the league who won the MLB All-Star Game, a rule which lasted until 2016.
In the American League, the New York Yankees made their ninth straight postseason appearance, the Oakland Athletics made their fourth straight appearance, the Minnesota Twins made their second straight appearance, and the Boston Red Sox made their fourth appearance in the last eight years.
In the National League, the Atlanta Braves made their twelfth consecutive appearance in the postseason, the Florida Marlins returned for the first time since 1997, the Chicago Cubs made their first postseason appearance since 1998, and the San Francisco Giants returned for the third time in four years. This was the last postseason appearance for the Marlins until 2020.
This was the last edition of the postseason to feature three 100-win teams until 2017.
The postseason began on September 30, 2003, and ended on October 25, 2003, with the Marlins defeating the Yankees in six games in the 2003 World Series. It was the Marlins' second title in franchise history.