Abstract: A cutting insert for a rotary milling cutter tool is described. The insert has a cutting edge defined between a cutting rake surface and a relief flank. The insert also has a base edge defined between the relief flank and a base surface. The cutting edge of the insert includes first and second successive component cutting edges which merge continuously with each other. The first and second component cutting edges have respective axial rake angles .gamma..sub.1 and .gamma..sub.2 with respect to an axis of rotation of the cutting tool, with .gamma..sub.1 being significantly greater than .gamma..sub.2. The relief flank and the component cutting edges are shaped and disposed so that the intersection of a plane passing through the rotational axis of the milling cutting tool with a surface milled by the cutting edge is substantially rectilinear.