A medical device and method are disclosed which can cause a filter included in a cylinder to capture a capturing target by causing a fluid including a circulating flow to flow inside and around the cylinder introduced into a living body. The medical device has a filter, a cylinder, and an impeller. The filter captures a capturing target present inside a living body. The cylinder includes a lumen having the filter arranged therein, an aspiration section, which is open on the distal side of the lumen, and a discharge section which is open on a side surface on a proximal side of the lumen. The impeller is arranged on a proximal side of the filter in the lumen, and causes the lumen to aspirate the capturing target together with a fluid by causing the fluid to flow from the aspiration section toward the discharge section inside the living body.
