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 was the second child of Kate (née Lamb) and John Hattil Foll; his father was a butcher.

He immigrated to Australia in 1909 with a friend and subsequently worked on Darr River Downs, a sheep station near Longreach in western Queensland.

In August 1914, Foll enlisted in the first Australian Imperial Force and landed on the first day of the Gallipoli campaign.

[3] From 1938 until 1941, Foll served as a cabinet minister during the Prime Ministerships of Lyons, Menzies, Page and Fadden.

[3] In 1942, Foll enlisted in the Volunteer Defence Corps, putting his age back by one year.

The following year, he acted as Leader of the Opposition in the Senate in the absence of John Leckie, who himself had been substituting for George McLeay.

He wrote to Menzies complaining of financial difficulties and asked for employment to be found within the Liberal Party organisation, but none was forthcoming.