A balloon catheter is provided with: an outer shaft (10) a balloon (20) an inner shaft (30) which is provided with an inner layer (31) not capable of being thermally bonded to the outer shaft (10) and which is also provided with an outer layer (32) capable of being thermally bonded to the outer shaft (10), the inner shaft (30) being inserted through the inside of the outer shaft (10) to form a guide wire lumen (30L), the inner shaft (30) having a distal end which opens as a guide wire port (35) and a connection tube (40) which consists of a resin capable of being thermally bonded to the outer shaft (10) and to the outer layer (32) of the inner shaft (30), the connection tube (40) being connected to the proximal end side of the inner shaft (30) to form the guide wire lumen (30L), the connection tube (40) having a proximal end which opens as a guide wire port (45). The balloon catheter is configured so that a reduction in the wall thickness of the inner shaft is capable of being suppressed or prevented during the production (thermal bonding step) of the balloon catheter and so that the jamming of a guide wire is capable of being prevented during the use (when expanding the balloon) of the balloon catheter.