Marlon Wayans' White Woman Dancing Tweet -- He Won't Apologize

Marlon Wayans made it clear to our photog ... he's unapologetic for generalizing about white chicks on the dance floor.

Marlon took a selfie at a Beyonce/Jay Z concert with a white woman dancing in the background and Instagrammed it with the caption, "UNRHYTHMIC WHITE WOMAN dancing next to me ..."

Marlon took a ration of crap from people who say he was racist. It didn't help that the chick was Australian singer Delta Goodrem, who's pretty popular.

Marlon was leaving Equinox gym in West Hollywood Wednesday when he made it clear ... he stands by his words.