The work aims to use H13 hot stamping die steel as the research material to explore the low temperature plasma nitriding process without formation of compound layer so as to improve the impact resistance and thermal fatigue resistance and prolong the service life. Plasma nitriding treatment was conducted to H13 steel specimen in a LD-8CL D. C. plasma nitriding furnace at 470, 490 and 510 ℃ for 8 h. The microstructure, phase composition, brittleness and thermal fatigue of H13 steel after plasma nitriding were tested and analyzed by optical microscope, X-ray diffraction, indentation test and self-designed thermal fatigue test. Compared with conventional plasma nitriding, H13 steel treated by low temperature plasma nitriding at 470 ℃ had no compound layer in the surface layer. The brittleness of the layer was significantly reduced and no cracks occurred around the indentation under the larger detection load. Meanwhile, the thermal fatigue resistance increased by more than three times. The 470 ℃ low temperature non-compound layer plasma nitriding was applied to the hot stamping die of vehicle plates to increase the service life about 5 times, from 18 000~20 000 pieces to 80 000~100 000 pieces. H13 steel after low temperature non-compound layer plasma nitriding at 470 ℃ has no compound layer on the surface, but has good toughness. Compared with the conventional plasma nitriding, the technology can significantly improve the thermal fatigue resistance and service life of die.