Joan Rosazza (born November 19, 1937) is an American former competitive swimmer who specialized in freestyle events. She is best known for her achievement at the 1956 Summer Olympics in Melbourne, Australia, where she won an Olympic medal.
Rosazza was a member of the United States Olympic swimming team for the 1956 Melbourne Games. She earned a silver medal as part of the U.S. women's 4 × 100-meter freestyle relay team. The American quartet, which included Sylvia Ruuska, Shelley Mann, and Nancy Simons, finished second behind the host nation Australia. Rosazza swam the second leg of the final relay. She also competed in the individual 100-meter freestyle event, where she advanced to the semifinals.
Born in Worcester, Massachusetts, Rosazza's early swimming career included training at the Worcester YMCA. Her collegiate athletic career included competing for Purdue University. Her contributions to the sport of swimming have been recognized with her induction into various halls of fame, including the New England Swimming Hall of Fame.