A catheter is provided with a flexible tubular member (4) having formed therein lumens extending in the axial direction thereof, and also with an operating wire slidably inserted in any one of the lumens and having one end connected to the distal end of the tubular member (4). The lumen through which the operating wire is inserted is formed at a position including the central axis of the tubular member (4). The tubular member (4) is formed by joining together a member (4a1) mounted on the distal side of the tubular member and having relatively high flexibility and a member (4a2) mounted on the proximal side of the tubular member and having relatively low flexibility. The distance from the proximal end of the tubular member (4) to a joint surface (80) between the members having different flexibility decreases stepwise or continuously in a specific direction.
