Benjamin Sebastian (June 11, 1741 – November 20, 1832) was a preacher, lawyer, merchant and one of the first judges on the Kentucky Court of Appeals (1792-1806). He was a participant in the Spanish Conspiracy (also called the Burr Conspiracy), a plan by a cabal of US planters, politicians, and army officers including Aaron Burr to establish an independent country in the southwestern United States (including the state of Kentucky) and parts of Mexico, united with the Spanish government of Louisiana.