PURPOSE: To form a flat joining part so that the packaging tube can cope with various types of bag lengths favorably while obtaining the pinching force of rolls firmly without generating an uneven contact, and perform the lateral sealing and cutting favorably.

CONSTITUTION: The vertical bag making-filling-packaging machine is equipped with rolls 34, 35 to pinch a packaging tube F', and at the same time, a lateral sealing-cutting device 20 is provided so as to adjust the high possively, and the length from the roll pinching location of a bag-packaged object to the lateral sealing-cutting location is adjusted to be shorter than the length of the bag-packaged object by the length of the lateral seal. When the rolls 34, 35 pulled down the packaging tube F' by a portion of one bag, a lateral sealing-cutting is performed, and after the rolls 34, 35 are separated, a liquid/fluid substance, etc., is filled. The rolls 34, 35 are linked to slide frames 32, 33, and separatable by the function of a linking mechanism 40 which is rocked by an air cylinder device 41, and turn at the time of pinching the packaging tube by the function of a shuttle type timing belt winding mechanism which is run by a servo motor 53, and a flat joining part A is formed by pulling down the packaging tube F'.