A packaging and filling device for forming a paper container, comprising: a loading means of taking out 1 out of a bundle of a plurality of blanks having vertically sealed and flatted, the loading means including a taking-out means which takes out the blank and has a making bendable means which bends the sixth panel of the paper container outward and makes the sixth panel bendable; an erecting means of erecting the flatted blank into the cylindrical blank; an infeeder which inserts a mandrel into the cylindrical blank with the sixth panel made bendable, a bottom forming means of forming a bottom of the cylindrical blank to form the paper container having a top opening and a bottom, the bottom forming means including the mandrel, a press station and a heating station; a filling means of filling liquid food through the top opening; and a top sealing means of heat-sealing the top opening; wherein the infeeder includes a carrier which moves together with the sixth panel of the cylindrical blank, and a prior bending block fixed to a position immediately before the mandrel, and as the carrier is moved downward, the sixth panel as well following the carrier to be bent with the corners of the forward end of the prior bending block; wherein 2 pointed claws being erected toward the third bottom panel; and the press station of the bottom forming means pressing the container bottom from the outside and the inside by the forward side surface of the mandrel and a press surface, characterized in that the making bendable means being a sector piece provided on the shaft of a rotary roller which receives and transfers the blank taken out, and provided at a position corresponding to the sixth panel; the heating station of the bottom forming means including a nozzle surface of a heat for heating the container bottom panel, and a bending claw provided on the nozzle surface for heating the inside surface of the third bottom panel, and including a triangular emboss provided on the forward side surface of the mandrel at a position corresponding to the sixth panel and abutting a position where the third bottom panel is exposed on the inside surface of the container. a loading means of taking out 1 out of a bundle of a plurality of blanks having vertically sealed and flatted, the loading means including a taking-out means which takes out the blank and has a making bendable means which bends the sixth panel of the paper container outward and makes the sixth panel bendable; an erecting means of erecting the flatted blank into the cylindrical blank; an infeeder which inserts a mandrel into the cylindrical blank with the sixth panel made bendable, a bottom forming means of forming a bottom of the cylindrical blank to form the paper container having a top opening and a bottom, the bottom forming means including the mandrel, a press station and a heating station; a filling means of filling liquid food through the top opening; and a top sealing means of heat-sealing the top opening; wherein the infeeder includes a carrier which moves together with the sixth panel of the cylindrical blank, and a prior bending block fixed to a position immediately before the mandrel, and as the carrier is moved downward, the sixth panel as well following the carrier to be bent with the corners of the forward end of the prior bending block; wherein 2 pointed claws being erected toward the third bottom panel; and the press station of the bottom forming means pressing the container bottom from the outside and the inside by the forward side surface of the mandrel and a press surface, characterized in that the making bendable means being a sector piece provided on the shaft of a rotary roller which receives and transfers the blank taken out, and provided at a position corresponding to the sixth panel; the heating station of the bottom forming means including a nozzle surface of a heat for heating the container bottom panel, and a bending claw provided on the nozzle surface for heating the inside surface of the third bottom panel, and including a triangular emboss provided on the forward side surface of the mandrel at a position corresponding to the sixth panel and abutting a position where the third bottom panel is exposed on the inside surface of the container.