The Distinguished Service Cross (DSC) is a third-level military decoration awarded for gallantry during active operations against the enemy at sea to officers; and, since 1993, ratings and other ranks of the British Armed Forces, Royal Fleet Auxiliary and the British Merchant Navy have been eligible.

It was renamed the Distinguished Service Cross in October 1914, eligibility being extended to all naval officers (commissioned and warrant) below the rank of lieutenant commander.

[4] From March 1915, foreign officers of equivalent rank in allied navies could receive honorary awards; in August 1916, bars were introduced to reward further acts of gallantry meriting the Cross, with a silver rosette worn on the ribbon when worn alone, to denote the award of each bar.

[4] During World War I, officers of the Merchant and Fishing Fleets had been awarded the DSC, and their eligibility was legally clarified by an order in council in 1931.

[5] In April 1940, equivalent ranks in the Royal Air Force serving with the Fleet could receive the DSC, and, from November 1942, so could those in the Army aboard defensively equipped merchant ships.

[4] Since the 1993 review of the honours system, as part of the drive to remove distinctions of rank in awards for bravery, the Distinguished Service Medal, formerly the third-level decoration for ratings, has been discontinued.