On 12 July 1950 three Canadian destroyers, HMCS Cayuga, HMCS Athabaskan, and HMCS Sioux sailed for Korean waters to serve under United Nations Command.  From then until the cease-fire in 1953, three Canadian warships on a rotation basis served continuously in the Korean War theatre.

The Royal Canadian Navy, along with navies of other UN Forces including the Republic of Korea, maintained blockades of enemy coasts, engaged enemy shore batteries, protected friendly islands, took part in the Inchon landing and, on the enemy East Coast had great success in "trainbusting"—the destruction of enemy supply trains.

On 27 July 1953, when hostilities ceased, 3,621 officers and men and a total of eight ships of the Royal Canadian Navy had served in Korean waters.