The present invention is a balloon catheter used primarily in treatment and surgery for the purpose of dilating lesion sites such as strictures or blockages in passages in the human body. The balloon catheter of the present invention has a structure wherein a guide wire passing tubular member is deployed passing through the interior of the expansion body, and the outer surface of the tubular member and the expansion body are concentrically fused near the distal end of the catheter. This is a balloon catheter that is characterized by the fact that the Shore hardness of the material configuring the outermost surface of the tubular member is smaller than the Shore hardness of the material configuring the expansion body. It is therefore possible to flexibly adjust the tip portion formed by securing the expansion body and the guide wire passing tubular member.