Professor Kilangi was born 6 April 1969. Kilangi was a member of the African Union Commission on International Law. He also served as the president of the commission from 2012 to 2014. Prior to the appointment he was also a director at St. Augustine University of Tanzania and served at various capacities at the university. In 2013 Kilangi released research work, "The Principle of Permanent Sovereignty over Natural Resources: Its Application in Regulating the Mineral Sector in Tanzania".