PROBLEM TO BE SOLVED: To provide a catheter with which the state of a shaft within a blood vessel can be checked by a simple constitution.SOLUTION: A balloon catheter 100 comprises: shafts 130 and 140; a balloon 120 provided on the distal side of the shafts 130 and 140; and a core metal member 170 provided inside the shafts 130 and 140 in the longitudinal direction of the shafts 130 and 140. Furthermore, the core metal member 170 is coated with X-ray impermeable material such as Au, Pt, Ir, and W.SELECTED DRAWING: Figure 2