Kevin Eugene Hagen (born March 8, 1960) is a former pitcher in Major League Baseball who played from 1983 through 1984 for the St. Louis Cardinals. Listed at 6' 2", 185 lb., Hagen batted and threw right-handed. He attended Bellevue Community College.

In a two-season career, Hagen posted a 3–2 record with a 4.25 ERA in 13 appearances, including four starts, giving up 17 runs (three unearned) on 43 hits and eight walks while striking out nine in 29+2⁄3 innings of work.