In 1970, Yoshio Unno started lecturing at the Tokyo National University of Fine Arts and Music. Five years later, he became the youngest full professor at the University at the age of 39. Tokyo District Public Prosecutors Office arrested the professor in 1981 on a suspicion of bribery over the school's purchases of musical instruments. Yoshio was sentenced to a year in prison with a three-year probation period; he left Japan and moved to Paris with his family. After the probation has expired, Unno returned to Japan in 1989.
From 2005 to 2011, Yoshio Unno served as a president of the Tokyo College of Music. The artist had been playing Antonio Stradivari's 1698 Thoulow violin since 1973.