The work aims to provide reference for optimizing cutting process of stainless steel 310S by revealing influence law of cutting depth ap, feed rate f and cutting speed v on surface integrity of stainless steel 310S. Milling experiment was performed to stainless steel 310S using coated carbide micro diameter cutter in response surface methodology (RSM). Then data and information regarding surface roughness, morphology and hardness were collected and analyzed. Multielement nonlinear regression was used, mapping relation between surface roughness Ra and cutting parameters were established, and significance test was performed to multielement regression equation. Significance of cutting parameter ap, v and f was 0.099, 0.620 and 0.011, respectively. Diagram of influence law of cutting depth ap, feed f and cutting speed v on the surface roughness Ra, surface morphology and hardness were plotted visually based on the experimental data and mathematical model of the surface response method. In a certain range of cutting parameters, feed rate f has the most obvious effects on surface roughness Ra of stainless steel 310S, followed by cutting depth ap, and little effects on cutting speed v. Cycloidal processing mark is left on the surface, there is more residue on the milling side than that on the reverse milling side. The cutting depth ap has the most remarkable influence on the hardness of 310S test piece, followed by the cutting speed. Reducing feed rate f is an effective processing method of reducing surface roughness of stainless steel 310S.