Mark Deady (born January 2, 1967) is an American Olympic middle-distance runner. He represented his country in the men's 1500 meters at the 1988 Summer Olympics. His time was a 3:41.91 in the first heat, and a 3:39.47 in the semifinals.
In 1985, Mark Deady was State Champion for Stevenson High School, Lincolnshire, Illinois. He was the Boys Class AA winner in the 1600 meter run. His time of 4:07.45 was a new State Record and stood until 2009 when Jeff Thode of J.B. Conan's High School ran to a winning time of 4:04.