Geller told the Jerusalem audience: “I have no problem in saying he is an antisemite. “God forbid if he takes control.”
Geller was asked by Rabbi Boteach if he thought it would damage his celebrity status if he spoke out by calling Mr Corbyn an antisemite.
Geller said: “I have charisma, if I said it, I would say it in the right way. I would have to say it live on TV in Britain and feel the Jewish people looking at me.”
Geller, who was once the subject of a documentary that claimed he used his telepathic and psychic powers in a number of key CIA operations during the Cold War, said he would make sure Mr Corbyn never became prime minister.
“With all my telepathic powers I am not going to let that happen,” he said.
He met Theresa May in 2014 and predicted she would become prime minister.
He said Mrs May came to meet him and he showed her his Cadillac covered in spoons, some of which were owned, used or touched by famous personalities.
He said: “I told her to touch Winston Churchill’s spoon. I told her she was going to be prime minister and she laughed.
“It is important that she stays in power because god forbid Corbyn should take her place.”