EXCLUSIVE

Rapper Juelz Santana has just been sentenced to 27 months behind bars in his airport drug case.

A judge handed down the sentence Wednesday morning in Newark, NJ. He'll also be under supervised release for 12 months after he's completed his time. No date was set on when the rapper will have to surrender.

TMZ broke the story ... Juelz was busted back in March after trying to take a loaded .38-caliber handgun and eight oxycodone pills in his travel bag at Newark International Airport. After TSA security found the gun, Juelz booked it but he later turned himself in.

The rapper -- a convicted felon -- ultimately pled guilty to unlawful possession of a weapon and possession of a controlled dangerous substance.