Allis is a surname. Notable people with the surname include:
Edward P. Allis, founder of what was to become Allis-Chalmers, and prominent in the Greenback Movement
Charles David Allis (born 1951), American biologist
John Allis (born 1942), American cyclist
Louis Allis (1916–1994), American industrialist and Wisconsin Secretary of State
Oswald T. Allis (1880–1973), American theologian
William Allis (1901–1999), an American theoretical physicist specializing in electrical discharges in gases
