Benjamin Carpenter (born circa 1713/14 – 8 March 1788) was a British soldier and courtier.
The son of Colonel Robert Carpenter, who was killed at the head of the 3rd Foot Guards at the Battle of Fontenoy in 1745, Benjamin Carpenter was for many years an officer of the 2nd Troop of Horse Guards, in which corps he rose to the rank of lieutenant-colonel. In November 1760 he was promoted to the rank of colonel, and appointed aide-de-camp to the King. He was promoted to the rank of major-general in 1762, and obtained the colonelcy of the 12th Regiment of Dragoons in 1764, from which he was removed to the 4th Regiment of Dragoons on 24 October 1770.
He was a great favourite with King George III, to whom he was made an equerry on 16 December 1760. He was appointed clerk marshal of the mews on 6 April 1771 and principal equerry in the royal establishment on 1 January 1783. Carpenter was promoted to the rank of lieutenant-general in 1772, and to that of general in 1783. In the seventy-fifth year of his age he became so depressed in spirits that his medical attendant directed his servants to watch his motions narrowly, but he eluded their vigilance, and proceeding to Hyde Park, about five o'clock in the morning of 8 March 1788, drowned himself in the Serpentine river.