HMS Namur was a 90-gun second rate ship of the line of the Royal Navy, built at Chatham Dockyard to the draught specified by the 1745 Establishment as amended in 1750, and launched on 3 March 1756. Namur fought in the Battle of Cape St Vincent (1797) under the command of Captain James Hawkins-Whitshed. Namur was astern of HMS Captain, under the command of then Commodore Horatio Nelson, at the beginning stages of the battle. Namur was razeed to a 74-gun ship in 1805, and was placed on harbour service in 1807. She remained in this role until 1833, when she was finally broken up.