Abstract: The problem of thin-walled aluminum alloy box parts due to thin side walls and milling deformation caused by the reduction of accuracy. A special fixture was designed and finite element analysis was performed, and the clamping deformation was reduced from 0.015 7 mm to 0.005 98 mm, a reduction of 61.9%; parameter samples were created and objective functions were generated by Design-Expert software, and an artificial bee colony algorithm was used to optimize the objective functions, and a set of milling parameters with the minimum milling force was obtained and the predicted values were output. ABAQUS software was used to simulate the output parameters, and the optimized results reduced the milling force of the thin-walled aluminum alloy box by 35.3%; finally, the actual machining experiments were conducted, and the dimensions of the parts were measured to be within the tolerance range. The study shows that the method is important for the thin-walled box parts to improve the machining dimensional accuracy.