To ensure the flexibility of a reduced diameter portion in a catheter having the reduced diameter portion that is reduced in diameter from the proximal end side toward the distal end side on the inner peripheral surface.A catheter includes an inner layer 50, a braid 52 corresponding to a first reinforcing body that is wound around the outside in the radial direction of the inner layer, a reinforcing member 64 that is wound around the outside in the radial direction of the braid, and an outer layer 62 that covers the inner layer, the braid, and the reinforcing member. The inner layer has a reduced diameter portion 60 that is reduced in diameter from the proximal end side toward the distal end side on the inner peripheral surface. The thickness of the outer layer between the braid corresponding to the first reinforcing body and the reinforcing member is increased, at least partially from the proximal end side toward the distal end side, in the radial direction of the reduced diameter portion. Therefore, in the radial direction of the reduced diameter portion, the layer between the braid and the reinforcing member functions as a cushion, whereby it is possible to ensure the flexibility of the reduced diameter portion.
