Young Dro Busted for Drugs

Rapper Young Dro is spending the night in jail after cops picked him up for a drug offense in Georgia ... TMZ has learned.

Clayton County Sheriff's Department says deputies arrested Dro around 3:30 PM Thursday and booked him for violating the controlled substance act. Unclear at this point where the Atlanta MC was, or what he was allegedly holding.

We're told he'll be in custody at least until Friday morning when he has a bail hearing.

We broke the story ... Dro also got arrested last summer for grand theft auto after some trickiness with a strip club employee.

And for what it's worth -- Dro has a show in Hollywood Thursday night -- safe to say he won't be making that.