A catheter which is one mode of a medical conduit of the present invention is placed inside a human body from the outside of the human body through human tissue. The catheter has a light introducing portion. The light introducing portion is provided on an outer wall surface of the catheter located on the outside-of-human-body side, and allows at least a part of ultraviolet light irradiated from the outside of the catheter to be totally reflected at an inner wall surface of the catheter toward the inside-of-human-body side.
