Houstoun is a surname. Notable people with the surname include:
John Houstoun (1744 – 1796), American lawyer and statesman from Savannah, Georgia Dr. William Houstoun (botanist) (1695–1733), British surgeon and botanist William Houstoun (lawyer) (1755–1813), American lawyer, Continental Congressman for Georgia Sir William Houstoun (fl. 1830s), British army officer, Governor of Gibraltar
See also Houston (disambiguation) Heuston, a surname