Abstract: The microstructures and the mechanical properties of 3Cr13 steel with different deep cryogenic treatment(DCT) have been investigated in this paper.The results revealed that the deep cryogenic treatment can improve the hardness of 3Cr13 steel variously.The impact toughness of 3Cr13 steels which were tempered at 180℃ for 8h after deep cryogenic treatment has not been improved.Meanwhile,the wear resistance of 3Cr13 steel could been obviously enhanced by various deep cryogenic treatment,and its mass lost ratio decreased significant to 40% after 6h deep cryogenic treatment.