The fourth HMS Diamond was a modified Lowestoffe-class fifth-rate frigate ordered in 1770, launched in 1774, but did not begin service until 1776.

Diamond was ordered on 25 December 1770 as one of five fifth-rate frigates of 32 guns each contained in the emergency frigate-building programme inaugurated when the likelihood of war with Spain arose over the ownership of the Falkland Islands (eight sixth-rate frigates of 28 guns each were ordered at the same time).

The contract to build Diamond was awarded to Hodgson & Co at Hull, the keel being laid in May 1771, and the frigate was launched on 28 May 1774, at a cost of £11,506.9.1d.

She sailed from Hull on 13 June 1774 for Chatham Dockyard, where she remained for nearly two years before she was completed and fitted out to the Navy Board's needs (for £4,169.8.6d) in February to May 1776.

[6] Diamond was paid off into ordinary in 1779, but after being coppered she was recommissioned in November 1779 under Captain William Forster, and sailed for Jamaica on 13 April 1780.