William Joseph Humphrey MBE (born 17 October 1967) is a former Democratic Unionist Party (DUP) politician who was a Member of the Northern Ireland Assembly (MLA) for North Belfast from 2010 to 2022. He was a Belfast City Councillor for the Court DEA from 2005 to 2014.

Born in the Woodvale area of Belfast, Humphrey studied at the Boys' Model School. A member of the Woodvale Residents' Association, he joined the Democratic Unionist Party, becoming its chairman in North Belfast, and a member of the party's executive.^[2] He was elected to Belfast City Council in the Court district at the 2005 Northern Ireland local elections,^[3] then served as High Sheriff of Belfast in 2006.^[4]

At the 2007 Northern Ireland Assembly election, Humphrey stood in North Belfast, but was not elected.^[5] He moved to contest West Belfast at the UK general election, 2010, but took only 7.6% of the votes cast.^[6] In June, he became Deputy Lord Mayor of Belfast.^[7]

In September 2010, he was selected to replace Nigel Dodds in the Northern Ireland Assembly, representing North Belfast^[2] and was elected at the 2011 Assembly election. Referencing his predecessor, Humphrey said, "Nigel has a proven track record of dedicated hard work on the ground, making a difference in peoples' lives within the Constituency...That will be the record I will strive to emulate."^[8]

Humphrey was appointed Member of the Order of the British Empire (MBE) in the 2021 New Year Honours for public service, particularly during the COVID-19 response.^[9]

In 2022, Humphrey announced that he would not contest the 2022 Assembly election.^[10]