Frederick Huntington Gillett (October 16, 1851–July 31, 1935) was an American politician during the early 20th century. He was born at Westfield, Mass., and educated at Amherst College and Harvard Law School. He began the practice of law in Springfield in 1877. He was Assistant Attorney General of Massachusetts in 1879–1882. For two terms he was a member of the Massachusetts House of Representatives, then became a member of the Fifty-third United States Congress.
He sat in the United States House of Representatives from 1893 to 1925, and then United States Senate from 1925 to 1931, as a Republican. He served as Speaker of the United States House of Representatives from 1919 to 1925.
In 1915 Gillett married Christine Rice Hoar, the widow of his former colleague Rockwood Hoar.