The work aims to explore the influence of milling amount on the surface quality of 7A09 aluminum alloy by analyzing the surface roughness, surface morphology and residual stress of the workpiece, so as to provide a certain theoretical basis for the control of the surface quality of 7A09 aluminum alloy. Method based on KVC800-1 CNC machining center, single factor method was used to test the plane milling of 7A09 aluminum alloy. Results the surface roughness of 7A09 aluminum alloy was improved with the increase of milling speed and decrease of feed per tooth. It can be seen from the 2D contour diagram and 3D surface topography diagram of the processed surface that the surface of the workpiece after milling has obvious furrows, and the wave peaks and troughs along the feed direction fluctuate within a certain range, presenting obvious regularity. When the amount of milling changed, the residual stress curve was distributed in the shape of a spoon, and the residual stress was more sensitive to the change of milling speed and the feed amount of each tooth, but less sensitive to the depth of milling. Conclusion by analyzing the influence of milling amount on the surface quality of processed 7A09 aluminum alloy, it can be concluded that the best surface quality can be obtained when the milling amount is vc= 240 m/min, fz= 0.14 mm/z, ap= 0.15 mm.