Military General; figure in the formation of the TKR General Headquarters in Yogyakarta. He was born in Purworejo, Central Java on 22 February, 1893 and he passed away in Yogyakarta on 17 November, 1948. Graduating from OSVIA Magelang (1910); he enrolled for a Islandsche Officier (19111914) course. He became a second lieutenant of the infantry and was assigned to Battalion XII and then to Southeast Kalimantan (1914-1917). In 1917, he successfully passed a test of equality to the Dutch officers. For 10 years, he kept moving from battalion to battalion and where he was assigned to. Returning as a major from his holiday to Europe, he was promoted to the commander of Depot Battalion II, which was his last position. From his own request, he retired with honor with pension rights and awards for his services (1938). He lived in Gentan, Jereng Mount Merapi, north of Yogyakarta. In 1940, he was exposed to the general mobilization and was recalled to serve again until the Dutch Indies Government/KNIL surrendered to the Japanese (March 1942). He became a prisoner to the Japanese for 3 months in Cimahi; then he returned to Genta without taking part in any activities from 1942-1945.

With the formation of the Republic of Indonesia (17 August 1945), he was called to form an army organization (Decree 5 October 1945 concerning TKR formation). A number of former KNIL officers were gathered for consultation; they stated that they were no longer tied to the oath of KNIL, and stood behind the government of the Republic of Indonesia. He formed the General Head Quarters of the National Army in Yogyakarta, and Oerip was appointed as the chairman of the General Staff on 20 October 1945. He passed away because of heart disease; his body was buried in the Semaki Heroes Cemetery in Yogyakarta. For his services, he was posthumously promoted to general; awarded with Bintang Sakti (1959); Bintang Mahaputra (1960); Bintang Republik Indonesia (1967); Bintang Kartika Eka Paksi Utama (1968); and promoted as a National Hero. To commemorate his services, his name has been immortalized as the name of a main road in Jakarta.