Alexander Raymond Kellner (August 26, 1924 – May 3, 1996) was an American starting pitcher in Major League Baseball who played for the Philadelphia/Kansas City Athletics (1948–1958), Cincinnati Redlegs (1958), and St. Louis Cardinals (1959). Kellner batted right-handed and threw left-handed. He was born in Tucson, Arizona. His younger brother, Walt, also was a major league pitcher.
In a 12-season career, Kellner posted a 101–112 record with 816 strikeouts and a 4.17 ERA in 1849-1/3 innings pitched.
Kellner died in Tucson, Arizona, at the age of 71.