Abstract: The invention provides a packaging bag for powdery or granular materials made of a plastic film having no air permeability, which is safe from the accident of bursting even when the bag filled with a powdery or granular material is laid at or near the bottom of a heap of such bags caused by the weight of the overlying bags. The inventive bag is provided with an air filter member bonded to the body of the bag in such a manner that the air inside the bag is communicated with the ambient atmosphere through the air filter member which is, for example, an open-cell foamed body of a plastic material.