It is well known that the life of TiN-coated hob becomes tremendously longer than that of non-coated hob. But even a TiN-coated hob, its rake surface must be resharpend when it was worn out. And then TiN-coating on rake surface is removed but only on flank surface. And TiN-coating on flank surface is still effective to decrease the flank wear. On the contrary, crater wear on rake surface of TiN-coated hob increases, same as that of non-coated hob. So, in high efficiency hobbing, the life of hob seriously depends on the crater wear. Here, the authors have clarified the shape of wear on TiN-coated hob to know its process and show some methods to increase the life of TiN-coated hob in case of high efficiency hobbing of the comparatively small module gears with TiN-coated and multi-start hobs that are often used for motorcycles and automobiles.