Herman Loin Humphrey (March 14, 1830 – June 10, 1902) was an American attorney, judge, and Republican politician. He served three terms in the United States House of Representatives, representing Wisconsin's 7th congressional district (1877–1883). Prior to his election to Congress, he was a Wisconsin circuit court judge for ten years in western Wisconsin, and served two years in the Wisconsin State Senate. Some sources give his middle name as Leon.