Provided is an expansive catheter balloon that has a spreadable outer diameter controllable easily in treatments for a calcific aortic stenosis, rheumatic and congenital aortic stenosis and others, and that can be effectively prevented from being freely shifted and can easily be fixed at a predetermined position. The catheter balloon includes a cylindrical balloon part that is made non-expansive or low-expansive, and a band part made of a stretchable elastic body. When a stretching force is not applied, the band part has a shorter diameter than a spread diameter of the balloon part and is wound around the center of the balloon part.
