Abstract: In order to improve residual stress numerical simulation accuracy of Zr-Sn-Nb alloy electron beam, thermophysical parameters and mechanical properties of Zr-Sn-Nb alloys and welded joints were measured. and the influence of the difference in joint properties on the residual stress of electron beam welded joints was investigated. The hybrid heat source model of electron beam welding is established, and the thermoelastic-plastic finite element method is used to numerically simulate the stress of electron beam welded 4.45 mm thick Zr-Sn-Nb alloy. The simulation model was verify by weld morphology. The results show that the peak transverse residual stresses in the weld and heat-affected zone region on the upper surface of the test plate are higher than those simulated when the properties of the two are the same, with peaks of 319 MPa and 296 MPa, respectively. The peak longitudinal stress was 318 MPa when the differences in the properties of heat-affected zone and the base material and weld are considered, which has little effect on the residual stresses in the joint.