Dr John Tierney (born 21 January 1946), Australian politician, was a Liberal member of the Australian Senate 1991 - 2005, representing the state of New South Wales.
Tierney was born in Cooma, and was educated at the University of Newcastle and the University of Sydney, gaining a Ph.D. in education. He was Senior Lecturer in Education at the University of Newcastle before entering politics.
Tierney was elected to the Senate in 1990, taking his seat in July 1991. In 1992 he was one of a group of Coalition members of parliament who founded the Lyons Forum, a conservative ginger group. At the 2004 election Tierney was dropped to fourth position on the Coalition Senate ticket in New South Wales and was defeated. He resigned from the Senate in early 2005.