The boxing great has tipped the UFC fighter to make the move to the ring on a permanent basis as he feels that The Notorious is better suited to boxing than MMA with his punching ability.
Foreman said: "It’s hard for McGregor to accept it but he’s a better puncher than he is in MMA. I’d rather see him in boxing matches now."
McGregor lost to Floyd Mayweather in a boxing clash in 2017 but Foreman has tipped the Irish fighter to beat Manny Pacquiao should they meet in the ring.
He told the Daily Star newspaper: "I think if he has a fight with Pacquiao he can actually beat him – good rules, over ten rounds, McGregor can beat him.
"He’s already adjusted to boxing, he’s not going to do good in MMA anymore.
"Pacquiao is very good as a matter of fact, but McGregor can beat him in a boxing match."
McGregor lost his most recent UFC clash with Dustin Poirier but the sport's boss Dana White expects that the pair will meet in a trilogy clash this summer.
He said: "They both want it.
"So when you’ve got two guys who want the trilogy as bad as those two do, we try to make it happen. It’ll happen this summer."