A study was made of the deterioration of two surface-treated hot-forging die steels after only a few forging cycles. The two surface treatments chosen for the study were chemical vapor deposition (CVD) of titanium nitride and the Toyota diffusion process for the formation of vanadium carbide. It was found that CVD titanium-carbide/titanium-nitride coatings and Toyota diffusion process vanadium carbide coatings significantly improved the wear resistance of both tool steels when used for hot-forging dies. Surface examination revealed that both coating systems reduced erosive wear, abrasive wear and central plateau cracking.