Mount Ibu (Indonesian: Gunung Ibu) is a stratovolcano located at the northwest coast of Halmahera island, Indonesia. The summit is truncated and contains nested craters. The inner crater is 1 km wide and 400 m deep, while the outer is 1.2 km wide. A large parasitic cone is located at the northeast of the summit and a smaller one at the southwest. The latter feeds a lava flow down the west flank. A group of maars are located on the western and northern side of the volcano.
August 2009 Volcanological Survey of Indonesia raised the eruption alert level for Ibu to "Orange".