A medical device includes a main body elongated in a vertical direction. A guide section protrudes from a lower end of the main body in a direction crossing the vertical direction and includes first and second guide holes. A first unit includes a first puncture needle slidably supported by the main body near an upper end of the first puncture needle in the vertical direction and having a sharp lower end slidably inserted into the first guide hole from above. The first unit has a first holding plate integrally fixed to the first puncture needle. A second unit includes a second puncture needle slidably inserted into the second guide hole from above and a second holding plate integrally fixed to the second puncture needle. The second holding plate separably abuts on the first holding plate from above. A position of the second guide hole is selectable along the guide section.
