kotamadya (municipality) in East Java (Jawa Timur) (Jawa Timur) propinsi (province), Java, Indonesia. The city lies on the east bank of the Madiun River. The population is mostly Indonesian and Chinese. The city was the scene of a short-lived communist rebellion, the so-called Madiun Affair, in 1948, and it maintains a site at which hundreds of soldiers killed in the Indonesian revolution are buried. The city is served by a main railway, and roads and an air service connect it to other towns.

The regency incorporates fertile plains in the north and centre, high volcanic peaks (Mount Lawu, 10,712 feet 【3,265 metres】) in the east and west, and limestone ranges to the south. Rice and sugarcane are the main crops, followed by corn (maize), cassava, coffee, cacao, cinchona, coconuts, and peanuts (groundnuts); teak comes from the forests. Madiun, a residency under the Dutch, was reduced in area under the Indonesian republic and became a regency. Area regency, 318 square miles (824 square km). Pop. (2005) 171,390.