Her task group staged at Ulithi, and arrived off Hagushi Beach, Okinawa on 1 April, screening the transport area as the initial assault was made. For the next 4 days, she guarded the transports off the beaches by day and during their night retirements, firing on the numerous "kamikaze" attackers. From 5 to 17 April, "Mustin" sailed to bring a convoy in from Saipan and Ulithi, then returned to fire support, radar picket, antisubmarine, and antiaircraft duty off Okinawa until 2 May, when she joined the screen of an escort carrier group operating to the southwest of Okinawa.