CUTTING INSERT

The present invention relates to a cutting insert. The cutting insert according to the present invention comprises: a top surface; a lower surface; a lateral surface for connecting the top surface and the lower surface; a hole penetrating through the top surface and the lower surface; and a cutting blade formed by the top surface and the lateral surface. The lateral surface of a main cutting blade among the lateral surfaces includes a first flank surface, a transition surface connected to the first flank surface, and a second flank surface connected to the transition surface. The first flank surface is formed in order for relief angle or flank face width to be changed along the cutting blade. A plurality of ridges is formed to be protruding for reinforcing the stiffness of the cutting blade at the transition surface.