To provide a new balloon catheter enabling formation of, with high dimensional accuracy and excellent shape adaptability with respect to a balloon, an additional structure such as a blade and a reinforcement member to be additionally provided to the balloon. In this balloon catheter 10 provided with an expandable/contractible balloon 14 on the distal end side of a catheter 12, an additional structure 36 having a prescribed pattern is formed through electroforming or the like directly onto an inner circumferential surface 34 and/or an outer circumferential surface 82 of the balloon 14.