Leszek Marian Kosedowski (born May 25, 1954 in Sroda Slaska) is a retired boxer from Poland, who won a bronze medal in the men's featherweight division (– 57 kg) at the 1976 Summer Olympics in Montreal, Quebec, Canada.
There he was defeated in the semifinals by the eventual silver medalist, Richard Nowakowski of East Germany.
His younger brothers, Krzysztof Kosedowski and Dariusz Kosedowski, were also boxers who competed in the Olympics for Poland.