A medical instrument includes: a jaw which is provided with a grasping section； and a blade which is movable close to and away from the grasping section and which extends from a distal-end portion thereof to a proximal-end portion thereof, the blade having a top portion including a ridge opposed to the grasping section, and the ridge of the top portion in the proximal-end portion being sharper than the ridge of the top portion in the distal-end portion.
