A balloon catheter has a balloon and an outer shaft fixed to a proximal end of the balloon. Each of the proximal end of the balloon and a distal end of the outer shaft has an inner projection extending in an axial direction of the balloon catheter, an outer projection extending in the axial direction, and a gap formed between the inner projection and the outer projection. At a fixing part, the inner projection of the balloon or the outer projection of the balloon is disposed in the gap of the outer shaft, and the inner projection of the outer shaft or the outer projection of the outer shaft is disposed in the gap of the balloon. The balloon catheter has improved fixing strength between the balloon and the outer shaft without increasing an outer diameter of the fixing part between the balloon and the outer shaft.