After her shakedown cruise on the Gulf Coast, Natchaug arrived at Port Arthur, Texas in late August and took on her first cargo, getting underway on the 28th.
Assigned to SERVRON 3, She provided support for Qingdao and Yokosuka, until returning to Guam on 3 April, her mission extended to include bases in the Palaus and the Admiralties.
Spending the first quarter of 1949 undergoing overhaul in San Francisco, California, she once again returned to Guam on 16 May 1949 as part of SERVDIV 51; with the Japanese Home Islands added to her mission of mobile fleet and base replenishment, serving COMNAV Marianas until the Spring of 1951, when she was reassigned SERVRON 3 to provide support for units within U.S. 7th Fleet, Task Force 90, and Task Force 95 in the Sasebo, Japan area.
She continued to serve bases in the Central and South Pacific Ocean up until February 1953, before steaming north to provide support for units in the Alaskan Sea Frontier.
She returned to Hawaii on 28 July after a visit to Hong Kong, China, resuming her duty of supplying Central and South Pacific bases.