Wichtiges Kulturgut Japans
Mutsuzawa is part of ancient Kazusa Province and has been settled since ancient times, and has several burial mounds from the Kofun period. Myōraku-ji, a temple founded in the Heian period, houses a wooden statue of the seated Dainichi Nyorai which has been designated one of the Important Cultural Properties of Japan. In the Edo period, Mutsuzawa was part of Ōtaki Domain. The villages of Tsuchimutsu, and Mizusawa were established with the creation of the modern municipalities system on April 1, 1889. The two villages merged on February 11, 1955 with a portion of the town of Chōnan to form the village of Mutsuzawa. It was elevated to town status on April 1, 1983.