Abstract: In order to optimize the film formation process of flaxseed gum and chitosan composite film,the composite film was prepared with flaxseed gum and chitosan as the main materials,and the effects of addition volume ratio of flaxseed gum solution to chitosan solution,chitosan mass concentration and glycerol addition on the performance of the composite film were investigated,and with the comprehensive score of composite film performance as the investigation index,the composite film preparation process parameters were optimized by principal component analysis and response surface method.The results showed that the optimal preparation process of the composite film were:flaxseed gum to chitosan volume ratio 20∶10,chitosan mass concentration 1.0 g/100 mL,and glycerol mass fraction 21%.The comprehensive performance score of the composite film was 0.724.The various indexes of the film were as followed tensile strength （18.16±0.17） MPa,elongation at break 57.15%±0.14%,water vapor permeability （1.30±0.02）（g·mm）（h·m~2·kPa）,oxygen permeability （7.30±0.08） cm~3/（m~2·d·Pa）,and light transmittance 95.55%±0.09%.Which can provide a theoretical basis for the application of composite film in food preservation.