HMS Vigilant was a 64-gun third rate ship of the line of the Royal Navy, launched on 6 October 1774 at Bucklers Hard. By 1779 she had been deemed unseaworthy by the navy. She was stripped of her sails and used as a floating battery to support the amphibious landing of British Army troops on Port Royal Island, South Carolina prior to the Battle of Beaufort. From 1799 she served as a prison ship, and was broken up in 1816.