Marlon Wayans Sued -- I Ain't No Cleveland Brown Lookin' N**** ... Says Actor

EXCLUSIVE

Marlon Wayans uncorked what seems like a hysterical comparison between an actor and Cleveland Brown -- but the actor's not laughing ... he's suing Marlon for racial discrimination and harassment.

Pierre Daniel says he was hired for a part in "Haunted House 2" -- written and produced by Marlon -- and last September Marlon posted a side-by-side pic of Pierre and the animated character Cleveland Brown on social media. The pic was captioned, "Tell me this n***a don't look like ... THIS N****!!! Ol Cleveland Brown ass lookin."

Honestly, seems like there's a slight resemblance -- but Pierre definitely didn't appreciate Marlon's joke.

In a lawsuit filed today in L.A. County ... Pierre claims Marlon's post was racially motivated and mocked his appearance. He also claims Marlon leered at him and rolled his eyes.

The lawsuit does not say where any of this went down -- but Pierre says the comparison seriously injured him by causing "shock, pain, discomfort and/or anxiety" ... and as a result he can no longer work as an actor.

He's suing Marlon and the movie's production company for unspecified damages.