The sailors' relatives, U.S. military officials and some 300 crew members of the guided-missile warship will join the private event, she added, without releasing other details.
The memorial comes as investigators probe into what happened in the early hours of June 17, when the ship collided with the Philippine-flagged ACX Crystal in a busy channel near the destroyer's home base, a gateway to container ports in Tokyo and nearby Yokohama.Rear Admiral Brian Fort has been appointed
to lead the U.S. investigation, the Navy said in a June 22 statement.
There have been around 30 ship collisions over the past decade in the area, including a 2013 incident in which six Japanese crew members died, according to the Japan Coast Guard.
The U.S. sailors, aged 19 to 37, were found by divers in flooded sleeping berths, a day after the collision tore a huge gash in the right side of the Fitzgerald.
Japanese investigators have interviewed the Filipino crew of the 730-foot cargo ship, while U.S. authorities are also probing the deadly crash.
The much-larger cargo ship's crew, who were not injured, apparently took nearly an hour to report the collision.
Japan's coast guard initially said the crash happened at 2:20 a.m. Saturday local time, based on when it was reported by the Crystal's crew. But they later told Japanese investigators the incident actually happened almost an hour earlier at 1:30 a.m.
Authorities are also investigating why the cargo ship made a sudden turn at about 1.30 a.m., and another sharp turn after it reported the accident at about 2:20 am.