John V. Nunziata (born 1955) is a Canadian politician. Nunziata started his career as a supporter of the New Democratic Party on a suburban Toronto city council. He left the NDP in 1982 after losing the nomination in the provincial riding of York South to the newly elected leader of the Ontario NDP, Bob Rae. Nunziata had felt that, by rights, the nomination should be his.

Nunziata joined the Liberal Party of Canada and was elected to the House of Commons in the 1984 general election despite a national Tory landslide. Nunziata thrived as an opposition member becoming a member of the Rat Pack, a group of Liberal MPs including Don Boudria, Brian Tobin, and Sheila Copps that made it their business to bring misery to the government of Brian Mulroney.

Nunziata ran as a candidate at the 1990 Liberal leadership convention, placing last. He alleged that the Liberals for Life , an anti-abortion group, had offered to support his candidacy in exchange for money. After the Liberals of Jean Chrétien won power in the 1993 Canadian election Nunziata was excluded from cabinet and became increasingly outspoken both with his social conservative views and his criticism of the Liberal government. On April 21, 1996, he was expelled from the Liberal caucus after he voted against the government's budget in protest over the government breaking a promise to rescind the Goods and Services Tax.

Despite the difficulties of winning a seat as an independent, Nunziata ran and won re-election in the 1997 general election without the support of any party. He was defeated in the 2000 election by Liberal Alan Tonks.

Nunziata ran to be mayor of Toronto in the 2003 municipal election as a right wing law and order candidate pledging support for the police and to sweep the homeless off the streets. Late in the campaign he claimed that the campaign of rival candidate John Tory had offered him $150,000 and the Deputy Mayor's position if he were to drop out of the race. Nunziata refused to release specifics, however, and a police investigation found no wrongdoing. Nunziata was accused of at best smearing his opponent with unsubstantiated claim, and at worst mischief, and his faltering candidacy scored barely 5% of the vote.

Nunziata's sister, Frances Nunziata, was the last mayor of the city of York, Ontario before it was merged into the megacity of Toronto, and is now a Toronto city councillor.