Henry Thomas Duffy KC (May 29, 1852 – July 3, 1903) was a Canadian politician. Born in L'Avenir, Lower Canada, the son of John Duffy and Mary Ann Mountain, Duffy received a Bachelor of Arts degree in English literature in 1876 and a Bachelor of Laws degree in 1878 from McGill College. He was called to the Quebec Bar in 1879 and practiced law in Sweetsburg, Quebec in the Eastern Townships.