Ralph Mattis (August 24, 1890 – September 13, 1960), known also as Matty Mattis, was a professional baseball outfielder whose career spanned seven seasons, one of which was spent in Major League Baseball (MLB) with the Pittsburgh Rebels (1914). In his only season in the majors, Mattis batted .247 with 14 runs scored, 21 hits, four doubles, one triple, and eight runs batted in (RBIs) in 36 games played. The majority of his career was played in the minor leagues.