"Guest" protected transports landing the Marine Raiders on Green Island 31 January 1944. As the Raiders reembarked the next morning, she made two depth charge attacks on a diving submarine. "Hudson" (DD-475) followed up this attack to complete the kill of the 1,400-ton Japanese submarine "I-171". "Guest" again screened transports during invasion of the Green Islands 15 February 1944. She bombarded Kavieng, New Ireland 25 February, and the Sanba River area on Bougainville 17 March. She rescued the crew of "PT-63" on the latter date. In a case of mistaken identity on 17 March motor torpedo boat PT-283 was sunk by friendly fire from destroyer Guest (DD-472), in the Solomons, near Choseul Island. Her 5-inch gunfire destroyed the grounded Japanese freighter "Meisyo Maru" 30 April to the east of Nemto Island. After amphibious assault training in the New Hebrides, she departed from Roi, in the Marshall Islands, 10 June 1944 for the invasion and capture of the Mariana Islands.