New method of nondestructive quality assurance was proposed and developed for ceramic coated tool materials like PVD/CVD TiN WC/Co cermets. Acoustic diagnosis on the basis of the acoustic spectro microscopy plays a main part of our developing method. Among various extended approaches in the acoustic diagnosis, this paper is concerning with the dispersion analysis of acoustic wave velocity for TiN coated WC/Co materials. Together with the elastic characterization of both WC/Co substrate and PVD/CVD coatings on their microstructural dependency of elastic properties, interfacial integrity was also investigated for TiN/TiC coated WC/Co. The Young's moduli of PVD/CVD TiN coating were estimated together with residual stress evaluation induced inside the coatings. The stress recovery was also quantitatively evaluated for heat treatment design of TiN-Ti(CN) coatings.