Elmer Joseph Cox (September 30, 1897 – June 1, 1966) was an American professional baseball player who played outfield for the Brooklyn Robins in 1925 and 1926.
He had a steady bat over his two seasons in the big leagues, batting .314 in 832 at bats, including eight home runs. Cox spent most of his time in right field defensively.
Prior to his playing days, Cox served in World War I.
He managed in the Arizona–Texas League in 1931 and 1932.