John James "Fats" Dantonio (December 31, 1918 – May 28, 1993) was an American Major League Baseball catcher for the Brooklyn Dodgers in 1944 and 1945.

Dantonio is one of many ballplayers who only appeared in the major leagues during World War II.

His career totals for 50 games include a .244 batting average (33-for-135), 12 runs batted in, 12 runs scored, a .301 on-base percentage, and a .304 slugging percentage.

As a receiver he was well below average, making 14 errors in 182 total chances for a low fielding percentage of .923.

This biographical article relating to an American baseball catcher born in the 1910s is a stub.