Abstract: ObjectiveThe preparation technology of chitosan based phlorotannins edible films was optimized,in or-der to provide theoretical references for the development and application of edible films.MethodUsing sodium carboxy-methyl cellulose(CMC)and chitosan as film materials,the edible films were prepared by tape casting method. With ten-sile strength,elongation at break and water vapor permeability as evaluation indexes,the optimal preparation conditions of edible films of chitosan based phlorotannins were determined by multi-index comprehensive scoring combined with or-thogonal test,and the properties of the edible films were characterized.ResultThe effects of each factor on physical properties of the edible films was ranked as follows:chitosan concentration>glycerol concentration>CMC concentration>polyacylphenol concentration,in which the chitosan concentration and glycerol concentration had significant effects on the physical properties of edible films(P<0.05). The optimal preparation conditions of edible films were obtained as fo-llows:chitosan concentration 1.5%,glycerol concentration 1.0%,phlorotannins concentration 0.4%and CMC concentra-tion 2.0%. Under the above optimum conditions,the edible films showed better physical properties with average tensile strength of 24.78 MPa,elongation at break of 36.94%,water vapor permeability of 0.445 g·mm/(m2·h·kPa)and com-prehensive score of 69.06. There were good compatibilities between components of the prepared composite edible films. The film surface was smooth and dense.ConclusionThe chitosan based phlorotannins edible films prepared by opti-mized technology have film-forming property and microstructure,which provides a new path for developing edible films.