The 1975 Boston Red Sox season was the 75th season in the franchise's Major League Baseball history. The Red Sox finished first in the American League East with a record of 95 wins and 65 losses. Following a sweep of the Oakland Athletics in the ALCS, the Red Sox lost the World Series to the Cincinnati Reds in seven games.

The American League East is one of Major League Baseball's six divisions. MLB consists of an East, Central, and West division for each of its two 15-team leagues, the American League (AL) and National League (NL). This division was created before the start of the 1969 season along with the American League West division. Before that time, each league consisted of 10 teams without any divisions.