Maruyama (丸山町, Maruyama-chō) was a town located in Awa District, Chiba Prefecture, Japan.

Maruyama was located at the southeast end of Chiba Prefecture, in an inland area of the southern Bōsō Peninsula, with a small shoreline facing the Pacific Ocean.

The town had a temperate maritime climate with hot, humid summers and mild, cool winters.

On March 20, 2006, Maruyama, along with the towns of Chikura, Shirahama, Tomiura, Tomiyama and Wada, and the village of Miyoshi (all from Awa District), was merged to create the city of Minamibōsō.

The economy of Maruyama was largely based on horticulture (primarily herbs and flowers), and summer tourism.