Abstract: Welding procedure test of 18CrNiMo7-6 with end-lock structure was carried out by vacuum electron beam welding. The microstructure and mechanical properties of vacuum electron beam welding joint of 18CrNiMo7-6were analyzed by microscopic examination, microhardness, tensile test, Charpy impact test and fatigue test.The results show that, the molten metal is cooled rapidly during welding, weld region is mainly composed of lat martensite, and HAZ is composed of martensite and ferrite. Hardness value of weld zone and HAZ is higher than that of base material, the tensile strength of joint reaches 950MPa, and the welding coefficient reaches 0.91. The impact performance of weld and HAZ is higher than that of base material. The fatigue limit is 354MPa, the fracture morphology shows obvious fatigue partition characteristics.