Returning to Norfolk, she had local patrol, sweeping, and training duty until 9 June, when she sailed for San Diego, California, and Pearl Harbor, arriving on 1 August.

For the next two months, she escorted convoys among the ports of New Guinea, aiding in the assembling of shipping for the Lingayen assault.

In company with six other minecraft, PC-1598 sailed from Ulithi on 19 March 1945 to sweep mines off Okinawa, clearing the way for both pre-invasion bombardment and the assault landings of 1 April.

She carried out her hazardous mission successfully, destroying many enemy mines, and sailed from the island on 5 April for a repair period at Guam.

PC-1598 gave patrol and escort services in the Marianas, and on 3 July she rescued a downed aviator.