The work aims to study effects of QPQ treatment on wear resistance of H13 steel at the nitridation temperature of 540 ℃. The microstructure morphology, composition distribution and phase composition of H13 steel subject to treatment were tested with SEM, EDS and XRD respectively. HVS-1000 microhardness tester and MFFT-R4000 high speed-reciprocated-wear experiment were used to analyze and study nitride layer thickness, microhardness distribution and wear resistance of H13 steel substrate and samples subject to QPQ treatment for different nitridation duration at 540 ℃. After the QPQ treatment, the uniform and dense (Fe3O4) oxide film, extreme hard ε-Fe3N and CrN compound layer as well as α-Fe and Cr2N stable diffusion layer were formed successively on H13 steel from the surface to center. N atoms were uniformly distributed inside. The microhardness had favorable gradient distribution along the cross section. Provided with the nitridation process of 540 ℃×4 h, subsurface microhardness of the layer reached the peak (1173HV0.1), 2.4 times higher than that of substrate (498HV0.1). Weight loss was only 1/13 of that of QPQ specimen. Serious plowing effect and plenty of wear debris, appearing to be typical abrasive wear accompanied with slight adhesive wear, were present on wear surface of H13 steel. Only adhesive wear appearing to be slight shallow scratches accompanied with few scar pits was present in the wear surface of QPQ treatment sample. After QPQ treatment, wear resistance of H13 steel is improved significantly, optimal performance is provided with nitridation process of 540 ℃×4 h.