The purpose of the present invention is to provide a filter device capable of reliably capturing an embolus, such as thrombosis or bubbles occurring in intra-blood vessel treatment or the like, and also reliably removing the captured embolus from the body. The present invention provides a filter device provided with: a first tube； a second tube protruding from the first tube； a filter arranged so that a tip side in the longitudinal direction becomes an opening part； a ring fixed to the opening part； a first wire protruding from the tip side in the longitudinal direction of the first tube； and a second wire protruding from a hole of the first tube and fixed to the ring, wherein the opening part can be opened and closed in the shape of an envelope when a base end side in the longitudinal direction is used as a bottom surface, and can be closed by pulling the second tube toward the base end side in the longitudinal direction.
