Abstract: Provided is a catheter with a novel structure which is able to allow its distal end portion to deform to curve more effectively in response to an operation from an outside. In a catheter 10, a control lumen 24 extending in a lengthwise direction is provided to an elongated shaft member 33, a control wire 54 is inserted through the control lumen 24, a fixing part 57 to which a distal end of the control wire 54 is fixed is provided to the shaft member 33, and an exposed part 60 is provided to a distal end portion of the control wire 54 over a predetermined length so as to be exposed through a window part 58 provided to a peripheral wall 28 of the control lumen 24 to a separate internal space 12 in the shaft member 33.