In this paper, the typical cold work die steel Cr12MoV was used as substrate material for vanadizing treatment. And the coating structure and bonding strength were studied. Moreover, comparison experiment of wear resistance between the coating and the substrate material was performed, and based on the experiment results, wear failure mechanism of vanadizing layer was analyzed. The results showed that vanadium carbide coating is dense, with fine grain structure and high bonding strength. These features help to improve the wear resistance of coatings. Comparision of wear performance between coating and substrate showed that vanadizing surface layer can significantly improve wear resistance of substrate material. Friction coefficient decreased from the 0.48 to 0.33 and wear weight loss decreased by 95%. Wear Failure analysis showed that the vanadium carbide layer of the wear mechanism is fatigue spalling wear.