Cormac Breslin (25 April 1902 – 23 January 1978) was an Irish Fianna Fáil politician. He was born in Gweedore, County Donegal. He was educated at Saint Eunan's College, Letterkenny. He was first elected to Dáil Éireann as a Fianna Fáil Teachta Dála (TD) for the Donegal West constituency at the 1937 general election.
Breslin was re-elected at every election until his retirement in 1977. He served as Ceann Comhairle (chairman) of Dáil Éireann from 1967 to 1973. He is credited for helping found the Industrial Estate in Gweedore, and also the turf burning station - a source of employment in his local parish, which allowed local people cut the turbary and sell it to the station operated by the Electrical Supply Board(ESB). situated in Min a Cuing , He was survived by his wife, Antoinnette (née Willman) and their nine children.