Abstract: The titanium alloy plate with the thickness of 50 mm were welded and surfaced by electron beam welding, and the residual stress distribution characteristics of the joints under heat treatment or non heat treatment conditions were measured by blind-hole method. The effect of post-welding heat treatment on the residual stress distribution was studied. The results show that in the weld and heat-affected zone, there are greater tensile stresses for the longitudinal stresses of the face of all joints, and there are whole compressive stresses for the transverse and longitudinal stresses of the back of all joints in which the distributions of the transverse stresses and longitudinal stresses are very close. The transverse stresses and longitudinal stresses of the joints under post-welding heat treatment tend to conform, and the stresses of the whole plates tend to homogenization.