The match played at the Stade Olympique de Rades was the second leg of the round of 16 in the Arab Champions League
The Ghanaian midfielder registered his goal in the 52nd minute to pull parity after the visitors had gone ahead in the first half.
The first leg also ended 1-1 in Morocco three weeks ago.
With the tie ending 2-2 on aggregate, the hosts bowed out of the championship after losing 4-2 on penalty shoot-outs.
Olympique de Safi advance to the quarter-finals of the competition.
Bonsu joined the Tunisian club in the summer transfer window from Kumasi Asante Kotoko after he had enjoyed a very successful season with the side in the CAF Confederations Cup.