Hattil Spencer "Harry" Foll (30 May 1890 – 7 July 1977) was an Australian politician who served as a Senator for Queensland from 1917 to 1947. He took office at the age of 27, and at the time was the youngest person to serve in the Senate. Foll began his career in the Nationalist Party, later joining the United Australia Party (UAP) in 1931 and Liberal Party in 1945. He held ministerial office as Minister for Repatriation (1937–1938), Minister for Health (1938–1939), Minister for the Interior (1939–1941), and Minister for Information (1940–1941). He was a member of the War Cabinet during World War II.