Jack Breheny
John Gerald "Jack" Breheny (17 May 1910 – 11 February 2009) was an Australian politician.

He was born in Toowoomba in Queensland. In 1951 he was elected to the Tasmanian House of Assembly as a Liberal member for Darwin (later Braddon) in a recount following Jack Chamberlain's resignation. He served until his defeat in 1972, and was then an Ulverstone councillor from 1976 to 1991. He died at Ulverstone in 2009.