HMS Sea Rover was a third-batch S-class submarine built for the Royal Navy during World War II.

Arriving in February 1944, the boat conducted several patrols in the Strait of Malacca, sinking one transport, one gunboat, one merchant, three sailing vessels, two coasters, and one lighter.

Sea Rover collided with an Australian corvette in December 1944, and she was sent back to England, then the United States, for repairs.

[6] On 5 July 1943, Sea Rover, under the command of Lieutenant John P. Angell (known as Peter),[7][8] sailed to Holy Loch, where she was commissioned into the Royal Navy two days later.

[10] Between July and September 1943, Sea Rover conducted exercises with various other submarines and surface ships off the River Clyde and Larne.

On 27 November 1943, Sea Rover was reassigned to the Pacific theater; she departed Holy Loch, and after a stay in Casablanca, left for Beirut on 22 December.

[9] On 1 April, Sea Rover departed on patrol off Diamond Point, Sumatra; on the 10th she fired six torpedoes at a large merchant vessel, but missed.

Four days later, she torpedoed the Japanese gunboat Kosho Maru south of Penang harbour while attacking a convoy of two merchant ships.

In the evening of 26 June, Sea Rover was depth charged by two Japanese anti-submarine ships south of Penang, sustaining considerable damage to internal fittings and instruments, as well as taking on two tons of water in flooding.

During her next two patrols, Sea Rover sank two small ships, but on 17 December the boat collided with HMAS Bunbury; temporary repairs were made to enable her to return to Britain.