Martin John Kennedy (August 29, 1892 – October 27, 1955) was an Irish-American politician from New York.

A real estate and insurance broker in New York City, Kennedy is most notable for his service as a Democratic member of the New York State Senate (1924-1930) and the United States House of Representatives (1930-1945).

He attended the public schools, and graduated from Columbia University in 1909; and from the College of the City of New York in 1914.

He served in the United States Army Intelligence during World War I; and was Chairman of the New York City School Board from 1918 to 1924.

Kennedy was elected as a Democrat to the 71st United States Congress to fill the vacancy caused by the resignation of John F. Carew, and was re-elected to the seven succeeding Congresses, holding office from April 11, 1930, to January 3, 1945.