Sukadji Ranuwihardjo (November 9, 1931 – August 11, 2007) was an Indonesian academic and former Rector (Head) of Gadjah Mada University (Universitas Gadjah Mada, or UGM) from 1973 to 1981. Sukadji was born on November 9, 1931 in Blitar, East Java in what was, at the time, the Dutch East Indies (present day Indonesia). He went to school, first, in Malang in East Java before moving to Gadjah Mada University in Yogyakarta to study economics. He later obtained a master's degree from the University of California, Berkeley, before completing a doctoral degree at UGM. His wife, Soetarlinah, was a psychologist, also a professor at Gadjah Mada University.