HMS Raisonnable (sometimes spelt Raisonable) was a 64-gun third rate ship of the line of the Royal Navy, named after the ship of the same name captured from the French in 1758. She was built at Chatham Dockyard, launched on 10 December 1768 and commissioned on 17 November 1770 under the command of Captain Maurice Suckling, Horatio Nelson's uncle. Raisonnable was built to the same lines as HMS Ardent, and was one of the seven ships forming the Ardent-class of 1761. Raisonnable was the first ship in which Nelson served.