Abstract: In this study, the processing flow and NC processing methods are sorted out and analyzed. The five-axis milling with dislocation and alternation of each lay is put forward to replace the layer milling of T-cutting with three-axis machining. After optimizing the processing flow, the semi-finish processing is merged with the finish processing which can reduce the clamping times and avoid the non-superposition error of benchmark. The experiment result shows that the optimized processing can improve the efficiency significantly and ensure the accuracy of the parts, which meets the requirements of design drawing.