The 1906 major league baseball season began on April 12, 1906. The regular season ended on October 7, with the Chicago Cubs and Chicago White Sox as regular season champions of the National League and American League, respectively. The postseason began with Game 1 of the third modern World Series on October 9 and ended with Game 6 on October 14. The White Sox defeated the Cubs, four games to two, capturing their first championship in franchise history. Going into the season, the defending World Series champions were the New York Giants from the season.
The 1906 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 .
National League Opening Day took place on April 12 with all teams playing, while American League Opening Day did not take place until April 14 with four teams playing. The final day of the regular season was on October 7. The World Series took place between October 9 and October 14.
20 tie games (12 in AL, 8 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 9 and ended on October 14 with the Chicago White Sox defeating the Chicago Cubs in the 1906 World Series in six games.
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Any team shown in indicates a previous team a player was on during the season.