HMS Saturn was a 74-gun third-rate ship of the line of the Royal Navy, launched on 22 November 1786 at Northam.

With the beginning of the War of 1812, Saturn was modified to become a frigate designed to take on large American vessels of that type.

Then under Captain Robert Lambert she sailed with Admiral Sir Hyde Parker's expedition to the Baltic.

[2] Saturn was cut down to create a rasée 58-gun spar-decked frigate in 1813 at the Plymouth dockyards in preparation for service in the War of 1812.

On 25 May 1814 Saturn captured the American privateer schooner Hussar, of 211 tons (bm), at 40°8′N 73°28′W / 40.133°N 73.467°W / 40.133; -73.467 after a four-hour chase.