To provide a bag for storing bags which makes it quick and easy to store a bag such as a shopping bag and put it in and take it out for recycling, takes up little space and has a nice appearance.

A storage device is used for storing a bag, such as a shopping bag, crumpled into a smaller size and consists of a cylindrical bag portion 1 and mouths 2, made in both ends of the cylindrical bag portion 1, through which the bag is put into the bag portion and taken out of it, and an elastic band is disposed along the openings 3 of the mouths 2. That is, such a bag as shopping bag is properly squashed with hands or tied round itself into a smaller shape and pushed into the mouth 2, thereby increasing the diameter of the mouth 2, and the bag is stored by being pushed into the bag portion 1. Here, the elastic band is disposed along the opening 3, therefore when the bag is pushed into it the opening becomes bigger and it makes it easy to store the bag, and once-stored bag is prevented from being pushed out. In the case the bag is necessary, the bag is taken out by inserting fingers from the mouth 2, and by pulling out the bag stored in the bag portion 1, thereby making the diameter of the mouth 2 bigger.