John Ritchie MacNicol (August 31, 1878 – June 18, 1950) was a Canadian politician. Born in Beaverton, Ontario, MacNicol was educated at public school, collegiates, and at Bryant & Stratton College in Buffalo, New York. He taught school in Algoma and Grey Counties, Ontario. From 1917 to 1920, he was president of the South York Liberal-Conservative Association. From 1921 to 1922, he was president of the Ward 6 Toronto Association. From 1921 to 1923, he was secretary of the Liberal-Conservative Association of Ontario and was president from 1923 to 1930. He was president of the federal Conservative Party from 1925 to 1943.