Joseph Marvin Coscarart (November 18, 1909 – April 5, 1993) was an infielder in Major League Baseball who played for the Boston Braves from 1935 to 1936. Coscarart batted and threw right-handed. He was born in Escondido, California. His younger brother, Pete, was an infielder who played with the Brooklyn Dodgers and Pittsburgh Pirates (1938–1946).
In a two-season career, Coscarart posted a .241 batting average with three home runs and 73 RBI in 190 games played.
Coscarart died in Sequim, Washington, at the age of 83.