This article examines the efforts and achievements of Oen Boen Ing, a Tionghoa doctor, to improve the quality of healt of the poorer inbitants of Surakarta. Dr Oen played an important role in five different periods: Duttch colonialism, the Japanese pccuption, the Indonesian revolution, Soekarno's regime, and Suharto's new order. Know for being a benevolent doctor, activist, and patriot of the revolution during his life-time, Dr Oen also gave medical assistance to the needy, which famously earned him the accolade of :doctor of the poor".During the Indonesian revolution, Dr Oen assisted the student Solidiers (tentara pelajar) and afterwand was appointed the member of supreme advisory council (dean pertimbangan agung/DPA) by Soekarno in1949. As a benevolent doctor and activist, Dr Oen is remebered for founding the pant kosala hospital after his passing. When he died, thausands of peoples gathered to pay their final respect to the doctor. He was honored with a ceremony conducted in the Mangkunegaran palace. Dr Oen's name wiil be eternally respected, especially in Surakarta.