After the outbreak of the Korean War in June 1950, William Andrewes was promoted to vice admiral on 1 December 1950.

On 17 December 1950 Andrewes was appointed commander of the 5th Cruiser Squadron and Flag Officer Second in Command Far East Fleet, flying his flag in the light cruiser Belfast.

he commanded British and Commonwealth Naval Forces,[4] with the carrier Theseus as his flagship.

He had two aircraft carriers available at any one time which he worked in eighteen-day cycles.

[5] and then Task Force 95 (comprising all Blockade and Escort ships in Korean waters, affiliated with the United Nations Command) in 1951.