Marcin Matkowski (; born 15 January 1981) is a Polish former professional tennis player whose speciality is in doubles. He played college tennis at UCLA, where Jean-Julien Rojer was one of his teammates. Matkowski and Mariusz Fyrstenberg won the Madrid Open twice, in addition to reaching the final at the US Open. The duo also reached the final of the ATP Finals and participated six times at the event overall. Matkowski won 18 doubles title in his career and achieved a highest ranking in doubles of world No. 7 in July 2012.