Thomas Grant waived a preliminary hearing before a Beaver County magistrate on Thursday.
Police say the girl was in a black costume with a white feather or tassel on her hat during a Halloween party at a New Sewickley home on Oct. 20.
The Beaver County Times reports investigators said the girl was lying face down and motionless during a game of hide-and-seek when she was shot.
Grant's attorney called the shooting a "tragic accident" and says his client's first concern is the girl's well-being. He says he'll ask to have the charges dismissed.
The girl is recovering from her wounds.