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The microstructure of electron beam welded GH4169D alloy was analyzed by optical microscope (OM) and scanning electron microscope (SEM). Micro hardness of fusion zone, heat affected zone (HAZ) and base metal were examined by micro hardness tester. The stress rupture characteristic of electron beam welded GH4169D alloy was researched by stereo microscope (SM) and SEM. The precipitated phases of GH4169D alloy are composed of lamellar η phase about 1~20μm in length, granular γ′ phase in size of 30~80nm, and a small amount of carbonitride. The precipitated phases of heat affected zone are mainly composed of granular γ′ phase in size of 10~20nm and few of η phase on grain boundary. Dendritic structures are formed in fusion zone, Nb, Ti, and Al are extensively rejected into the interdendritic liquid and the eutectic constituents are form in size of 2~6μm. There are fine granular γ′ phase in size of 10nm in gamma dendrites. The micro hardness of base metal is lower than that of heat affected zone and fusion zone. Micro hardness of different zone is depend on the particle size of γ′ phase. Stress rupture process is composed of creep crack growth, rapidly crack growth and final fracture. Intergranular fracture is occurred in creep crack growth zone, mixed of intergranular and transgranular fracture is occurred in rapidly crack growth zone and transgranular fracture is occurred in final fracture zone. The creep crack imitated in the surface of HAZ of weld specimen. Because of low content of intergranular η phase and oxidation of grain boundary in crack tip, the stress rupture life and elongation are lower than those of GH4169D base metal.