Marcel Mart (born 10 May 1927 in Esch-sur-Alzette) is a retired Luxembourgish politician, jurist, and businessperson.
A member of the Democratic Party, Mart served in the government under Pierre Werner (1969–1974) and Gaston Thorn (1974–1977). In 1977, he was named as Luxembourg's representative in the European Court of Auditors, in which he sat for two six-year terms, during which time he also served as President (1984–1989).