The 1907 major league baseball season began on April 11, 1907. The regular season ended on October 6, with the Chicago Cubs and Detroit Tigers as regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the fourth modern World Series on October 8 and ended with Game 5 on October 12. The Cubs defeated the Tigers, four games to none (with one tie), capturing their first championship in franchise history. Going into the season, the defending World Series champions were the Chicago White Sox from the season.
The Boston Beaneaters renamed as the Boston Doves.
The 1907 schedule consisted of 154 games for all teams in the American League and National League, each of which had eight teams. Each team was scheduled to play 22 games against the other seven teams of their respective league. This continued the format put in place for the season. This format would last until .
Opening Day took place on April 11 with all but the Brooklyn Superbas and Boston Doves playing. The final day of the regular season was on October 6. The World Series took place between October 8 and October 12.
30 tie games (18 in AL, 12 in NL), which are not factored into winning percentage or games behind (and were often replayed again), occurred throughout the season.
The postseason began on October 8 and ended on October 12 with the Chicago Cubs defeating the Detroit Tigers in the 1907 World Series in five games (one of which being a tie).
<section begin=Bracket/> <section end=Bracket/> Note: Game 1 ended in a tie.
Any team shown in indicates a previous team a player was on during the season.