This paper is intended as an investigation of high temperature behavior of TiC films deposited on the SKH9 tool steels by PECVD. Vacuum annealing of SKH9/TiC samples was performed in the temperature range of 700∼1000℃, and the variation in chemical composition and state was studied by AES, RGA and XPS analysis, and also micro hardness and scratch test was conducted. By vacuum annealing, Ti/C ratio of TiC films became about 1, and chlorine and oxygen contents in the films decreased. The chemical state of chlorine in the TiC lattice was Ti-Cl or Ti-C-H-Cl banding and evaporated to form Cl₂ or HCl with vacuum annealing. Oxygen formed TiO₂, TiO_xCl, H₂O and Ti-C-H-O compound. With the increase of the annealing temperature, the amount of TiO₂ bonding increased, but total oxygen content in the films decreased because of evaporation of H₂O or decomposition of TiO_xCl and Ti-C-H-O bond. Judging from the above results, it is obvious that hydrogen exists in the TiC films. Also, The micro hardness and critical load of TiC films decreased with the vacuum annealing.