Alphonso George Kellam (born in Livingston County, New York November 23, 1837; died in Spokane, Washington, June 15, 1909) was an officer in the American Civil War, a lawyer, a politician, and one of the original justices of the South Dakota Supreme Court. Kellam was married in October 1865 to Clara Cole in Smithfield, New York. They had one son, Fred W. Kellam, a lawyer in Spokane.