Matthew James Foster (born January 27, 1995) is an American professional baseball pitcher who is a free agent.

[1] Foster split the 2016 season between the Arizona League White Sox and the Great Falls Voyagers, going a combined 0–0 with a 0.61 ERA over 29+2⁄3 innings.

[11] He made his MLB debut on August 1, pitching a scoreless inning of relief and earning a win in the process.

[12] With the 2020 Chicago White Sox, Foster appeared in 23 games, compiling a 6–1 record with 2.20 ERA and 31 strikeouts in 28+2⁄3 innings pitched.

Foster appeared in just 37 games in the Major Leagues compiling a 2–1 record with a 6.00 ERA in 39 innings while striking out 40 batters.