1945–1951

As an APD, her primary role was to land raiding parties on enemy beaches and Underwater Demolition Teams (UDT) personnel on beach obstacle clearance operations. APDs also retained the sound gear and some anti-submarine weapons of destroyer escorts, and served as escorts to amphibious groups. Because they could take on extra personnel, they were often designated as rescue ships if a transport went down.

After shakedown out of Guantanamo Bay, Kleinsmith arrived at Norfolk, Virginia, on 21 July. Departing on 4 August for the Pacific, the high-speed transport steamed via the Panama Canal, San Diego, and Pearl Harbor, and reached Buckner Bay, Okinawa, on 1 October. She operated between Okinawa and the Japanese home islands until 21 February 1946. She then sailed from Sasebo via the Marshall Islands and Pearl Harbor, arriving at San Francisco on 24 March with 118 returning veterans embarked. Departing on 10 April, she proceeded via the Panama Canal to the East Coast, arriving at Norfolk on 1 May 1946.

Based at Norfolk and NAB Little Creek, during the next six years, Kleinsmith operated along the Atlantic coast from Labrador to Venezuela while conducting amphibious and anti-submarine operations. She served primarily as an amphibious command ship; many of her cruises carried her into the Caribbean, where she operated out of Puerto Rico, the Virgin Islands, and Guantanamo Bay.

1951–1960

During January 1951, the Kleinsmith embarked an Underwater Demolition Team (UDT) at Little Creek to participate in the filming of The Frogmen, a Hollywood film chronicling the adventures of the Navy's UDT divers in the Pacific during World War II. Departing Norfolk on 3 January 1951, the warship stopped at Key West, Florida, and Charlotte Amalie, St. Thomas, United States Virgin Islands, before commencing ten days of filming between 15 January and 6 February. According to the command historian, "Dana Andrews and Richard Widmark helped make the old 'klinker-dinker' a movie star."

Returning from the Caribbean on 13 February 1951, Kleinsmith departed Little Creek on 5 March on the first of four deployments to the Mediterranean Sea. Arriving at Gibraltar on 15 March with UDT personnel embarked, she deployed with the 6th Fleet and participated in amphibious operations that ranged from Oran, Algeria, to Phaleron Bay, Greece. After serving as an amphibious control ship, she departed Gibraltar on 26 June for the United States, arriving at Little Creek on 6 July. On 19 July 1952, she departed for another four-month deployment with the 6th Fleet, and supported its important peace-keeping activities off the troubled lands of the Mediterranean.

Returning to Little Creek on 29 January 1955, Kleinsmith resumed operations along the eastern seaboard to the Caribbean. On 9 January 1957, she again departed for duty with the 6th Fleet, and for almost three months operated in the Eastern Mediterranean. In response to an urgent request from King Hussein of Jordan, whose government was threatened with leftist-oriented, Egyptian-supported subversion, Kleinsmith departed La Spezia, Italy, on 25 April for the Levantine Coast. Arriving off Beirut, Lebanon, on 30 April, she joined ships of the 6th Fleet in a formidable display of seapower, designed to show U.S. determination that the integrity and independence of nations in the Middle East would be guaranteed against Communist subversion or aggression. Remaining on station until 3 May, she then departed Rhodes, Greece, on 18 May, and returned to Little Creek on 1 June.

Less than three months later, Kleinsmith sailed once again for the Mediterranean, arriving at Palermo, Sicily, on 15 September. During the previous August, a pro-Soviet takeover of the Syrian Army had threatened the stability of the Middle East. The high-speed transport proceeded to the Eastern Mediterranean on 19 September, and operated there to prevent aggression and to preserve peace. She departed Barcelona, Spain, on 4 November, and arrived back at Little Creek on 17 November.

In 1958, Kleinsmith continued her activities along the Atlantic coast. While operating out of Guantanamo Bay on 24 October, she rescued 56 U.S. citizens and 3 foreign nationals at Nicaro, Cuba, where they were endangered by military operations between the Cuban Army and the Fidel Castro's rebels. From 27 May to 3 August 1959, she cruised to the Great Lakes via the newly opened St. Lawrence Seaway. On 1 April 1960, Kleinsmith departed Little Creek for the Pacific. Steaming via the Panama Canal, San Diego, Pearl Harbor, and Guam, she arrived Tsoying, Taiwan, on 15 May. Kleinsmith was decommissioned on 16 May 1960, and was transferred the same day to the Nationalist Government of the Republic of China.

Tien Shan moored, date unknown

ROCS Tien Shan

The ship served in the Republic of China Navy as ROCS Tien Shan (APD-315), (later renumbered 215, 615, and 815). In the early 1970s, Tien Shan was fitted with a second 5-inch/38 mount aft, a Sea Chaparral surface-to-air missile launcher, and ASW torpedo tubes. At this time, she was re-rated as a patrol frigate. In the 1980s, Tien Shan, and other surviving ships of her class which were also transferred to Taiwan, were assigned to the Customs Service Coastal Patrol command, where they patrolled the economic exclusion zone. In this role, their armament was reduced to just one twin 40 mm mount in front of the bridge. She was still active in this role in 1995. Her decommissioning year is variously reported as 1997 or 1998.