Abstract: A cemented carbide tool of excellent wear resistance and fracture resistance includes a substrate of cemented carbide, and a ceramic coating layer by chemical vapor deposition. The thickness of the layer is in the range of between 2 .mu.m to 20 .mu.m, and the layer has cracks of such a depth that the cracks extend perpendicularly from a surface of the layer to the substrate. The cracks are formed in a network-like pattern to minutely divide the layer. The average value of the depths of the cracks in a direction perpendicular to the surface of the layer is not less than the thickness of the layer and not more than a value equal to the coating thickness plus 5 .mu.m. The average value of widths of the cracks is not more than 2 .mu.m. The average value of intervals between the cracks is not less than 10 .mu.m and not more than 100 .mu.m.