Mount Merbabu (Indonesian: Gunung Merbabu) is a dormant volcano in Central Java province on the Indonesian island of Java. The name Merbabu may be translated as "Mountain of Ash," from the Javanese words "Meru," meaning "mountain," and "awu" or "abu," meaning "ash."

Mount Merapi, an active volcano, is located directly to the southeast of Merbabu. The city of Salatiga is found on the northern foothills of Merbabu. A wide area about 1,500 meters high lies between Merbabu and Merapi. This area includes the village of Selo, Java, and is known for its very fertile farmland.

The volcano has two peaks: Syarif, which is 3,119 meters high, and Kenteng Songo, which is 3,145 meters high. Three U-shaped valleys extend from the Kenteng Songo summit in the northwest, northeast, and southeast directions.

Two moderate eruptions are recorded: one in 1560 and another in 1797. The 1797 eruption was rated as a 2 on the volcanic explosivity index, which describes eruptions as explosive. A possible eruption may have occurred in 1570, though this is not confirmed.

Recent eruptions from Merbabu came from a fissure system that ran from the northwest to the southeast across the summit. This system sent lava flowing from Kopeng and Kajor craters on the northern and southern sides of the volcano, respectively.

People can climb Merbabu from several routes. One route starts from the town of Kopeng on the northeast side, and another begins from Selo on the southern side. A climb from Kopeng to Kenteng Songo takes about 8 to 10 hours.

In 2004, an area covering 57 square kilometers (22 square miles) around the mountain was declared a national park.