Lee Roy Mahaffey (February 9, 1904 – July 23, 1969) was a pitcher in Major League Baseball. He played for the Pittsburgh Pirates, Philadelphia Athletics, and St. Louis Browns. His key pitch was a fast-breaking curveball. In nine seasons, Mahaffey posted a 67-49 record with a 5.01 earned run average in 1,056 innings pitched with 365 strikeouts. As a hitter, Mahaffey posted a .184 batting average (73-for-396) with 28 runs, 4 home runs and 33 RBI in 224 games pitched.