Margaret Osborne duPont (born Margaret Evelyn Osborne; March 4, 1918 - October 24, 2012) was a World No. 1 American female tennis player.
DuPont won a total of 37 singles, women's doubles, and mixed doubles Grand Slam titles, which places her fourth on the all-time list despite never entering the Australian Championships. She won 25 of her Grand Slam titles at the U.S. Championships, which is an all-time record.