Lady Gaga's driver was pulled over Wednesday night after nearly running over a fan outside the Chateau Marmont.

The eccentric singer had left Crustacean restaurant in Beverly Hills ... then spent time hanging out at the Chateau. While she was leaving the Hollywood hot spot, the scary incident took place.

The X17 photographer on the scene tells us:

    "One of Gaga's bodyguards blocked the street with a brand new Rolls Royce. That's when her driver almost hit a fan in the street. The pedestrian called the cops and the driver's SUV was pulled over. Cops spent quite a while questioning the driver while Gaga sat in the backseat."

See a photo of Gaga leaving Crustacean ... after the jump.