DJ Khaled -- Accused of Biting Gold Chain Pose from Up and Coming Rapper Kolley

DJ Khaled jacked his new hardcore cover art over from another rapper, who happens to be an up and comer named Kolley -- but the up and comer has lawyers ... and TMZ has learned they're taking legal action.

Here's the deal ... Kolley dropped his debut mixtape, "RNS" about 6 weeks ago ... with a pretty distinctive cover shot (left) -- a closeup of his face, clenching a gold chain in his matching gold grill.

Cut to this week ... when DJ Khaled released "They Don't Love You No More" with artwork that's pretty much identical to Kolley's

We're told Kolley's peeps at Bigg Bank Entertainment just sent a cease and desist letter to Khaled's label ... warning them to stop using the cover art STAT or face a legal s**tstorm.