"We were made aware of rumours of sexual harassment at his last place of work," Wits spokesperson Shirona Patel told The New Age newspaper.
"They confirmed that these were true. We then interviewed him again and he admitted that he was dishonest. He was fired on the spot."
The university was also reportedly investigating claims of sexual harassment made by three students against a drama lecturer.
Although a charge had not been laid with the police, the drama lecturer was confronted and suspended on Friday.
Patel said Wits hoped to have a resolution by June.