To prevent defective seals fouled by a seal part of a bag body and the damages caused by the collision with a solid by providing a filling nozzle having an inner nozzle for filling the solid and an outer nozzle for filling a liquid to surround the outer side of the inner nozzle on the bag body having an upwardly directed opening part.

After a bag body 4 is installed below a filling nozzle 1 with an opening part 4a formed on one end thereof directed upward, a liquid is supplied to an outer nozzle 3. After the liquid is supplied to the outer nozzle 3, a solid is supplied to an inner nozzle 2. The solid supplied into the inner nozzle 2 is supplied to the bag body 4 through the opening part 4a while forming a flow passage F2 surrounded by a flow passage F1, and as a result, a content C containing the liquid and the solid is filled in the bag body 4. Thus, the previously supplied liquid works as a buffer, and the bag body 4 is prevented from being damaged by the dropped solid. Even when the solid is supplied after the liquid is supplied, generation of splash is prevented by the presence of the flow passage F1.