Boston (along with Canberra and Chicago) was not recommissioned for service during the Korean War as were 10 others of her class, but was earmarked for conversion to carry guided missiles and reclassified CAG-1 on 4 January 1952. In February 1952 she was towed from Bremerton, Washington, to Philadelphia for conversion to a guided missile heavy cruiser by New York Shipbuilding Corporation, Camden, New Jersey. During conversion her aft 8-inch turret was replaced with Terrier Surface-to-air missile launchers and she was modernized. Boston was recommissioned 1 November 1955 as the lead ship of her class and operated along the east coast and in the Caribbean conducting missile evaluations and participating in fleet exercises until departing for the Mediterranean 23 November 1956. She returned in May 1957.
