Following shakedown training and operations out of Naval Amphibious Base Little Creek at Virginia Beach, Virginia, LST-1157 departed Morehead City, North Carolina, on 25 September 1953 with a full load of United States Marines and amphibious vehicles for transfer to the United States Pacific Fleet and arrived in San Diego, on 25 October 1953.

In the Far East, Terrell County participated in a wide variety of operations with beachings and landings of embarked United States Marines and their equipment.

Occasionally, maneuvers with warships of other Southeast Asia Treaty Organization (SEATO) member countries took place in locales ranging from Thailand to South Korea and from Borneo to the Philippine Islands.

Operational commitments subsequently overrode refresher training out of Yokosuka in July, forcing the ship to embark Naval Beach Group 1.

Finally, both ships were forced to maneuver radically to avert a collision, with the Soviet vessel passing close aboard at Terrell County's port aft quarter.

For two months, Terrell County supported operations in Quảng Trị Province, just south of the demilitarized zone (DMZ), and conducted a series of landings in rapid succession: Bear Chain, Kangaroo Kick, and Belt Drive, before heading for Hong Kong on 19 September 1967.

Following visits to Okinawa and Subic Bay, Terrell County loaded ammunition and causeway sections and departed Yokosuka on 1 March 1968, bound for Vietnam.

Arriving at Da Nang on 13 March, she delivered her causeways and proceeded to Tien Sha to unload her ammunition and to take on the gear necessary for her forthcoming operations.

Joining the Amphibious Ready Group once again, Terrell County operated off Mỹ Thủy, South Vietnam, from 15 March to 12 April 1968 before retiring to Subic Bay.

She rendezvoused with the landing platform helicopter USS Valley Forge off Vietnam on 29 April 1968 for operations on station in area "Alice".

Subsequently sailing for Hong Kong on 12 May for a five-day visit, Terrell County headed for Buckner Bay, Okinawa, to deliver cargo from Da Nang before moving to Yokosuka for an overhaul which lasted through the summer of 1968.

From 1 to 7 December 1968, Terrell County conducted general drills and gunnery exercises before beaching at Vũng Tàu to load ammunition.

As a result of these operations, VC extortion from local South Vietnamese foresters and fishermen in the lower Cà Mau peninsula was substantially, albeit temporarily, curtailed.

Training and local operations in Japanese, Okinawan, and Philippine waters preceded yet another Vietnam deployment which commenced upon Terrell County's arrival at Vũng Tàu on 8 May 1969.

With 50 men of the Mobile Strike Force embarked, as well as a U.S. Army scout helicopter and a U.S. Navy Underwater Demolition Team (UDT) detachment, Terrell County provided support for multifaceted operations designed to destroy VC factories, training and supply camps, and extortion stations.

The ship subsequently carried causeways to Da Nang, Vietnam before resuming duties as support LST for continued interdiction and pacification operations at her old haunt, Cà Mau.

During this period, Terrell County established regular mail deliveries to off-shore units by helicopter, the first such services provided in the Cà Mau vicinity.

Loading troops and equipment on 30 November 1969, she got underway on 1 December 1969 to neutralize a threatened mortar attack before returning and refueling from SS Hampton Roads.

The rescue and salvage ship USS Deliver, also in the area, soon retrieved the tow, and thus allowed Terrell County to proceed to Chu Lai.

After loading U.S. Marine Corps and U.S. Navy vehicles, Terrell County departed Chu Lai on 6 October 1970 for Subic Bay.

After off-loading her cargo on 13 November 1970, Terrell County proceeded to San Francisco, California, for four days liberty before continuing northward.

Transferred, on loan, to Greece under the Security Assistance Program, she was renamed Oinoussai (L104) in Hellenic Navy service and was stricken from the Naval Vessel Register on 1 November 1976.