HMS Melampus was a 46-gun modified Leda-class fifth-rate frigate built for the Royal Navy during the 1810s.

Completed in 1820, she was not commissioned until 1845 for the South America Station and was converted into a store and receiving ship in 1855.

[1] The modified Leda-class frigates were armed with twenty-eight 18-pounder cannon on her gundeck, fourteen 32-pounder carronades on her quarterdeck and a pair of 9-pounder cannon and two more 32-pounder carronades in forecastle.

[2] She was completed for ordinary at Plymouth Dockyard 2–23 September 1829 and was roofed over from the mainmast forward.

[1] Melampus's first commission began on 12 March with Captain John Campbell in command and she was ready for sea on 18 May.