Following outfitting, Benewah remained at Boston serving with the Atlantic Reserve Fleet as a barracks ship for the crews of aircraft carriers going out of commission.

The barracks ship remained in reserve at Boston until February 1947 when she was moved to the St. Johns River waterfront facilities of Naval Auxiliary Air Station Green Cove Springs, Florida.

On 22 August, she departed Norfolk for Naples, Italy, where she served as flagship for the Commander, Fleet Air, Eastern Atlantic and Mediterranean.

On 30 September, Benewah began her second deactivation overhaul at Staten Island, New York, in the yard of the Brewer Dry Dock Company.

The barracks ship was decommissioned sometime in December 1955, and was berthed with the Green Cove Springs Group, Atlantic Reserve Fleet.

In July 1966, Benewah entered the Philadelphia Naval Shipyard for conversion and modernization preparatory to her return to active service.

In 1967-69, Benewah spent most of its time in the Mekong River near the 9th Infantry Division base at Đồng Tâm or an alternate anchorage near Bến Tre.

In addition to serving as headquarters, she provided barracks space, medical facilities, stores issue and a myriad of other services to the sailors and soldiers operating with the Mobile Riverine Force and with the similar formations that succeeded that organization when it was disestablished late in August 1969.

In May and early June 1970, Benewah participated in the Cambodian Campaign to support forces interdicting the Viet Cong supply lines running through that country.