PURPOSE: To prevent a checker from interfering with the existence of s clamp for supporting a bag when the weight of the whole body of a bag is measured by a checker which is provided in the middle of a circular orbit.

CONSTITUTION: A packaging device dispense an object to be packaged in a bag which is opened at point C while a bag 25 being fed to clamps 20 from the outside at point A are supported and being carried. For such a packaging device, the clamps 20 are opened only for a specified period of time at point E, and at the same time, the bag is supported by a pair of movable jaws which are provided on a metering mechanism while the clamps are opened, are the weight of the bag is measured by the weighing mechanism 40. Then, the error between the weight measured by the weighing mechanism 40 and the target weight which is previously stored in a control unit 61 is calculated, and the object to be packaged the amount of which is equal to the weight shortage found by the calculation is supplemented in the bag by a weighing supplementing mechanism 63.