The invention discloses a storage device for welding shielding gas. The storage device for the welding shielding gas comprises an arc body. A pre-storage cavity is formed in the arc body, a gas outlet cavity is connected to one end of the arc body, a hanging plate is connected to the other end of the arc body, the hanging plate is connected with an external semitight mechanism through a transverse rod in the working process, and a gas hole is formed in the end of the gas outlet cavity. The storage device for the welding shielding gas further comprises rolling wheels, the rolling wheels are arranged at the connecting portion of the pre-storage cavity and the gas outlet cavity and are hinged to the inner wall of the two sides of the pre-storage cavity through supporting rods, the axial centers of the two rolling wheels are connected though a connecting rod, a spring is arranged on the top of the pre-storage cavity, and the spring is connected with the middle of the connecting rod. The rolling wheels directly make contact with the outer surface of a steel pipe when the steel pipe makes contact with the arc body, sliding friction between the arc body and the steel pipe is changed into rolling friction, the spring can be compressed when the rolling wheels move up continually, the connecting rod is limited from ascending continually when the maximum extend is reached, and influences on the rotation of the rolling wheels due to the contact of the rolling wheels and the inner wall of the pre-storage cavity are avoided.