An object of the present invention is to provide a balloon catheter integrated with a guidewire in which a stepped portion is prevented from being formed between a coil portion of the guidewire and a front end portion of the balloon catheter and thus crossability of the balloon catheter is improved. The balloon catheter includes a transition part made of resin that smoothly connects an external shape of an outer coil of a front end coil part and an external shape of a tip portion of a front side inner shaft.