A press release to the media said the decision was taken after a special meeting by the Governing Council on July 30, 2015.
Professor Avoke will take over from Professor Akwasi Asabere-Ameyaw whose tenure of office ends on September 30, 2015.
The council has also appointed Mr Viscount Buernortey Buer as the new University Librarian with effect from October 1, 2015.