John Thomas Haig, PC QC (December 15, 1877 – October 23, 1962) was a politician in Manitoba, Canada. He served as parliamentary leader of the Manitoba Conservative Party in 1921–22. Born in Colborne, Ontario, Haig received his BA from the University of Manitoba, was called to the Manitoba bar in 1904 and worked as a Barrister-at-law. In 1907, he married Josephine M. Dickie. He was elected to the Winnipeg Public School Board in 1908, and continued to hold this position after entering provincial politics, also serving as board chairman. In 1927, Haig was named King's Counsel. He was president of the Manitoba Curling Association and of the Assiniboia Lawn-Bowling Club.