To solve a problem of a conventional shopping bag with two wheels or a handcart wherein the shopping bag itself is a load when going shopping.

The shopping bag has four casters, and the length of a handle part and a drawing part can be adjusted. The shopping bag is characterized by using a bag strap tape instead of a steel or plastic pipe to draw the shopping bag. When the shopping bag has no content but the body itself, a user can carry the shopping bag on the shoulder or hang it by the arm if very small casters are used. A bag with space on the bottom for storing the casters is manufactured, a basket with casters is put in the bag, and the casters are taken out of the space on the bottom of the bag. The basket is attached to the bag with strings, etc. attached in the interior of the bag, so that the shopping bag is finished three-dimensionally. It is preferable that the casters should be made of rubber which hardly makes sound, and the bag body should be made of a waterproof fabric. The shopping bag also has a cover and a pocket for storing the cover in case a zipper can not be easily closed because of a heavy load.