John Hemphill (December 18, 1803 – January 4, 1862) was an American politician and jurist who served as Chief Justice of the Supreme Court of the Republic of Texas from 1841 to 1846 and of the Supreme Court of Texas until 1858, and a United States senator from Texas from 1859 to 1861.
A member of the Democratic Party, he was one of the signatories of the Confederate States Constitution.