MGK Defends Himself Against Rabid Fan at Forbes Summit in Ohio

Machine Gun Kelly got more than he bargained for at the Forbes Under 30 Summit ... after an aggressive fan dashed onstage and nearly came face-to-face with him!!

The musician was being interviewed Tuesday by Forbes Editor Kristin Stoller in front of a packed crowd at the Cleveland Public Auditorium in Ohio.

Suddenly, the crazed man darted up to MGK onstage and started saying something to him. MGK jumped to his feet and confronted the dude, giving him a tongue-lashing.

Check out this video ... which shows MGK making his hands into fists while telling the guy, "My man, get the f**k away from me."

It didn't stop there as MGK continued ... "Yo, what are you doing? What are you doing? This is a bad look. Don’t make me do this."

A security guard then came out and grabbed the guy, hauling him away.

MGK then sat back down and apologized to everyone for his "primal reaction." But no one seemed bothered by his response, including Stoller, who gave MGK props for how he handled the situation.

After getting kicked out of the venue, the troublemaker was surrounded by security personnel on the sidewalk. TMZ obtained video of him sitting on the ground with his back against a wall as the guards stood over him waiting for police to arrive.