After recommissioning 15 July 1949, Heron engaged in training exercises on the U.S. West Coast until 4 October 1950, when she sailed for Korean War duty.

She patrolled off the Korean Peninsula and was of invaluable assistance for her clearing of channels for blockading ships in the siege of Wonsan Harbor in March 1951.

[2] She maintained surveillance of North Korean sea traffic after the Armistice until January 1954, when she retired to Sasebo, Japan, for training duties.

Reclassified MSC(O)-18 on 17 February 1955, Heron decommissioned again 21 March, and was turned over to the Japanese Maritime Self Defense Force the same day to serve as Nuwajima (MSC-657).

Heron was returned to U.S. Navy custody 31 March 1967, struck from the Naval Vessel Register the same day, and used as a fire target by the Japanese Maritime Staff Office.