A "Girls Gone Wild" crew member allegedly went a little too wild with a young woman -- and now he's paying the price.

Suffolk County, NY cops popped Matthew O'Sullivan last night after a 20-year-old woman accused him of "unwanted sexual contact" that took place after she was invited onto the infamous bus. The "GGW" machine was in Smithtown, Long Island at a place called Nubar.

O'Sullivan was charged with Criminal Sexual Act in the first degree, and will be arraigned today in Central Islip. A "GGW" rep didn't immediately comment.