The South Bend Blue Sox was a women's professional baseball team who played from 1943 through 1954 in the All-American Girls Professional Baseball League. A founding member, the team represented South Bend, Indiana, and played their home games at Bendix Field (1943–1945) and Playland Park (1946–1954).
The Blue Sox was one of two teams to play in every AAGPBL season, the other being the Rockford Peaches. Often a second-division team, they appeared in six playoff series and won two league titles.
In the 1943 inaugural season, The Blue Sox finished in third place with a 51–40 mark, only .001 percentage point behind second place Kenosha Comets. Together, pitchers Margaret Berger and Doris Barr threw 79 of the 91 games played by the Sox. Berger was credited with 25 wins and Barr with 15, while Berger posted her greatest triumph in a 13-inning match, which she won 1–0.
The next three years, South Bend finished 64–55 (1944), 49–60 (1945), 70–42 (1946), 57–54 (1947) and 57–59 (1948). After falling in their playoff intents, in the 1949 season the team posted the best record in with a 75–36 mark. That year they were swept in the playoffs, 4-to-0, by Rockford, after getting a first-round bye along with them. The South Bend club went on to win their next four playoffs in claiming back-to-back championship titles in 1951 and 1952. After that, the Blue Sox finished in last place both in the 1953 and 1954 seasons.