Abstract: For the non-segmented welding V-shaped large thin plate parts, vibration and stress deformation are easily occur in the milling processing process, resulting in the parts scrap. In this paper, on the basis of introduction of the processing deformation factors, a V-shaped large thin plate parts processing deformation control problem is effectively solved through formulating reasonable processing process, making the corresponding special tooling, optimizing tool path and CNC program parameters, and other schemes. It would provide a feasible processing technology scheme for meeting the product design requirements.