On 30 May "Manley" joined Task Group 52.15 (TG 52.15) and departed for the invasion of Saipan. The high-speed transports arrived off Saipan on the night of 14 June and landed their marines on established beaches south of Garapan on 16 June. Thereafter, except for a trip to Eniwetok for supplies and night harassing fire on Tinian Town and airports on the nights of 9, 12, and 18 July "Manley" operated in the transport screen until 22 July. She returned to Eniwetok on the 22nd and, after a trip to Kwajalein, sailed to Pearl Harbor, arriving on 9 August, she began preparations for the next operation.