Michael Brennan (died 6 October 1970) was an Irish politician who served as a Teachta Dála (TD) for fifteen years for the Roscommon constituency.
Brennan was first elected as an independent TD to the 5th Dáil Éireann in the June 1927 general election and returned to the 6th Dail in the September 1927 general election.
After losing his seat in the 1932 general election, Brennan joined Cumann na nGaedheal and was returned to the 8th Dáil in the 1933 general election. He was re-elected in 1937 general election to the 9th Dáil and in the 1938 general election to the 10th Dáil. He lost his seat in the 1943 general election, and stood again unsuccessfully as a Fine Gael candidate in the 1944 general election.
He stood as an independent candidate in the 1948 general election, and for Fine Gael in the 1951 general election, but was unsuccessful on both occasions.