TiAlSiN coatings with different Al content were prepared by hollow cathode discharge ion plating (HCDIP) and medium frequency magnetron sputtering ion plating (MFMSIP) hybrid physical vapor deposition (PVD) coating system. The composition, microstructure, mechanical properties of these coatings were systematically investigated by means of EDX, XRD, SEM, nanoindentation, scratch and tribological tests. It was found that the coatings had (111) or (200) preferred orientation with addition of Al. Proper content of Al led to increase of microhardness and adhesion. The flank wear of carbide end mill coated with TiAlSiN had the least wear than those coated with TiAlN and TiSiN coatings under the high speed milling of hardened steel experiments.