Cutting device according to an embodiment of the present invention is a cutter apparatus having a pocket for receiving the insert into the body and clamp the insert by the wedge is fixed to the screw, the insert, and a parallel top and bottom surfaces, the opposite sides each other, any one pair of the opposite side as a parallelepiped shape are formed with a groove extending in the longitudinal direction, opposite side of the other pair of the cutting edge is formed at the upper and lower edges, it said pocket has two side walls, and then the rear wall, and is formed in a bottom wall, a front and upper face is opened, one side wall is formed with a guide projection of a shape that is structurally suited for the groove formed in one side surface of the insert extends in a longitudinal direction, and the other side wall is upwardly inclined slope is formed, the wedge is secured by screws, one side is structured to conform to the groove formed at the other side of the insert Is guided to form the projections extend in the longitudinal direction, the other side is characterized in that formed in the downward inclined surface which is structured to meet the inclined surface of the pocket. Cutter device according to the invention has an effect that is significantly shorter insert replacement.