Following the outbreak of war in Korea in June 1950, "McKean" joined the 7th Fleet in August. Her commanding officer was Cdr. H. L Reiter, Jr., USN. She was assigned to Task Force 77 initially as part of DesDiv 112. She participated in the Inchon invasion which spearheaded the ground offensive operations against the North Korean Communists. Later, while steaming independently off the Chinnampo River, she discovered the first minefield reported during the Korean War. Commander John Weatherwax took command of "McKean" in November 1950. From October 1950 to December 1950, she joined patrolling destroyers with Task Force 72 in the Taiwan Strait with the light cruiser , and the destroyers , , and . They had to battle Typhoon Clara which broke apart into two typhoons.