Harold Arthur Clement Machin (May 9, 1875 – October 13, 1931) was an Ontario lawyer and political figure.
He was also a Ku Klux Klan organizer who attempted to start a chapter in Winnipeg, but was unsuccessful.
Machin who was born in England and grew up in St. John's, Newfoundland and Port Arthur, Ontario.
He served overseas with a Canadian labour battalion and with the British Army during World War I.
After quitting the Conservative Party, he ran as an independent in the 1919 Ontario election, but was defeated by labour candidate Peter Heenan.