Maria Margareta of Dietrichstein (Maria Margareta Josefa; 18 April 1637 – 15 December 1676), was a German noblewoman by birth, member of the House of Dietrichstein, and by marriage Princess Montecuccoli and Duchess of Melfi.
She was tenth child and sixth (but fifth surviving) daughter of Maximilian, 2nd Prince of Dietrichstein zu Nikolsburg, and his first wife Anna Maria, a daughter of Karl I, Prince of Liechtenstein and Duke of Troppau and Jägerndorf.[1][better source needed][2]