Cormac Michael Breslin (25 April 1902 – 23 January 1978) was an Irish Fianna Fáil politician who served as Ceann Comhairle of Dáil Éireann from 1967 to 1973. He served as a Teachta Dála (TD) from 1937 to 1977.
He was born in Bunbeg, Gweedore, County Donegal.
He was first elected to Dáil Éireann as a Fianna Fáil Teachta Dála (TD) for the Donegal West constituency at the 1937 general election. He was re-elected at every election until his retirement in 1977, switching constituency to Donegal South-West in 1961 and to Donegal–Leitrim in 1969. He served as Ceann Comhairle of Dáil Éireann from 1967 to 1973, and as Leas-Cheann Comhairle from 1951 to 1967. He is credited for helping found the industrial estate in Gweedore,