The present invention provides a coated
cutting tool in which fracture resistance and
wear resistance are simultaneously realized, tool life is improved, and
surface roughness of machined workpiece is improved The coated
cutting tool is provided with hard
coating layer 2 on substrate 1. The substrate 1 is formed of a binder phase comprising one or more kinds of iron-group metals and a hard phase comprising one or more kinds of substances selected from the group consisting of carbides, nitrides, and oxides of the
periodic table IVa-, Va-, and VIa-group elements, and
solid solutions thereof. In the
coating layer 2, blade-edge
ridge 3, a range of at least 200 mum from the rake face side boundary 6 of the same
ridge toward the rake face side, and a range of at least 50 mum from the flank side boundary 7 of the same
ridge toward the flank side are formed to be smooth surfaces which substantially have
surface roughness (Rmax) of 0.2 mum or less (reference length: 5 mum).