Arriving at Pearl Harbor on 26 October she was assigned to night radar picket duty and on 15 November she sortied for the invasion of the Gilbert Islands.

Dionne screened a group of tankers serving the ships engaged in this operation until her return to Pearl Harbor on 12 January 1944 for repairs.

After an overhaul at Mare Island, California, from 9 March to 8 April she sailed to Kwajalein and Eniwetok as convoy escort, then returned to Pearl Harbor on 10 May to rehearse amphibious landings.

After escorting ships to Eniwetok and Saipan, she returned to Pearl Harbor on 23 November as screen for Salmon (SS-182), damaged by Japanese depth charges, and Holland (AS-3).

Dionne served in anti-submarine warfare exercises and amphibious training in the Hawaiian Islands until 20 January 1945 when she began convoy duty between Pearl Harbor and Eniwetok.

On 25 July she departed Ulithi to join the oilers serving the 3rd Fleet during their strikes on the Japanese mainland, duty which occupied her until the end of the war.