"Sea Dog" remained based at Key West into the fall of 1955 when she was ordered to New London, Connecticut, to begin inactivation. Arriving early in December, she proceeded to the Portsmouth Naval Shipyard in Maine for overhaul in January 1956; and, in May, she returned to New London, where she was decommissioned on 27 June. She remained in the New London Reserve Group until partially activated in February 1960 for service as a Naval Reserve training ship in the 1st Naval District. She served in that capacity until struck from the Naval Vessel Register on 2 December 1968. She was docked in Salem, Massachusetts as a floating museum until 1973 when she was sold for scrap.