Mamoru Seki (関 衛, Seki Mamoru) was a dive bomber pilot officer in the Imperial Japanese Navy (IJN) during World War II. He is best known for being the commander of the dive bomber squadron of carrier Shōkaku and for leading strikes against United States Navy (USN) carriers in both Battle of the Eastern Solomons and Battle of the Santa Cruz Islands, where they severely damaged Enterprise on two occasions. He was killed in action during the Battle of the Santa Cruz Islands.