<p>[Problem] To provide a medical device which is capable of supporting smooth insertion of a medical apparatus into a living body and of removing extraneous matter that attaches to the medical apparatus without taking out the medical apparatus from the body. [Solution] This medical device (100) comprises: a long main body (20); a distal end part (10) which is disposed on the distal end side of the main body and has a flat part (11) that spreads in the surface direction; a flow path (30) which extends from the base end side of the main body to the distal end part and extends, via the distal end part, to the base end side of the main body and is capable of circulating a fluid; an insertion part (50) which is disposed at the distal end part and into which a medical apparatus can be inserted such that a site of the medical apparatus to be cleaned faces the flow path; and a guide part (60) which guides the insertion of the medical apparatus into the insertion part.</p>
