In wire arc additive manufacturing, residual stress is generated from a nonuniform thermal distribution, resulting in the fabricated component demonstrating large deformation. This study explored the effects of electroshock treatment (EST) on the residual stress and geometric dimensions of additive manufacturing components. A special and innovative stress frame was built with wire arc additive manufacturing, on which the EST was conducted. Changes in the residual stress, geometric dimensions, temperature, microstructure, and dislocation distribution on the stress frame during processing were investigated. According to the experimental results, it was concluded that the dislocation density decreased and that the distribution was more homogeneous after EST, which was affected by electron wind force. Finally, the residual stress was reduced, and the geometric dimensions were improved on the substrate.