The 6-foot-5 guard from France said his top option remains returning for his junior season.
"I love the coaches, the school and my teammates," he said. "There is still a lot of uncertainty with what might happen to next year's NCAA season, so entering the draft gives me a little more time to evaluate that."
He added that he will work with coach Mark Few and the staff in reaching a decision before the draft's withdrawal date.
Ayayi is the second Gonzaga player to declare for the draft without hiring an agent, joining Corey Kispert.
Ayayi started 23 of 33 games last season, averaging 10.6 points and 6.3 rebounds. He was voted the most outstanding player of the West Coast Conference tournament.
Ayayi enjoyed a breakout season after averaging 1.7 points in limited action as a freshman.