Electron beam welding of TC11 alloy was carried out to study the microstructure, mechanical properties and residual stress of the joint. In the fusion zone, typical columnar crystals with fine martensite α′ are found, in contrast with the heat affected zone where equiaxed α and martensite α′ are dispersed in the transformed β. The microhardness of the fusion zone is higher than that of the heat affected zone and the base metal. The joint impact toughness is increased by 20%, while the tensile strength remains invariable compared to the base metal. Longitudinal and transverse stresses are tensile, while the transverse stress is smaller than the longitudinal stress.