John James Hemphill (August 25, 1849 – May 11, 1912) was a U.S. Representative from South Carolina.

He attended public schools and was graduated from the University of South Carolina at Columbia in 1869.

He served as chairman of the committee on the District of Columbia (Fiftieth and Fifty-second Congresses).

He was an unsuccessful candidate for election as United States Senator from South Carolina in 1902.

[5] Hemphill married Addie Avery, granddaughter of John Motley Morehead, of Morganton, North Carolina.