The utility model relates to a mouth is so that put into the mechanism is opened to mouth at bottom of portable paper bag machine of end card at the bottom of automatic opening portable container bag, and this mechanism is opened to mouth at bottom of portable paper bag machine is including the conveyer belt, the conveyer belt passes through the power supply to be realized carrying, its characterized in that: the mouth is sent the direction here and is equipped with the guide slot at the bottom of the container bag of conveyer belt top edge, the guide slot is formed by outer baffle and interior baffle, outer baffle is installed in the frame, interior baffle is installed in the conveyer belt top to and there is the clearance between the conveyer belt, width phase-match after the mouth is opened at the bottom of the width of guide slot and the container bag. According to the utility model provides a mechanism is opened to mouth at bottom of portable paper bag machine can automatic open end mouth in the transportation process of portable container bag, and end mouth is opened the back and is just put into end card by putting end card mechanism, then in proper order through rubber coating and hem, last compaction shaping, from this the completion whole work of the portable container bag of end card have.