Abstract: An apparatus for automatically filling bags with a material after separating each bag from a continuous chain of bags along perforations where each bag is joined to its neighbor has a guide section for guiding the chain of bags, a separating section for separating the chain of bags into individual bags at the perforations, a mouth opening device for opening a mouth located at one side edge of each bag, and a filling section for blowing air into the bag through its opened mouth and for filling the bag through the opened mouth. The mouth opening device has a pressing assembly supported above the mouth of the bag, and a chuck assembly situated at one side of the mouth.