The work aims to improve physicochemical properties of composite edible films based on three kinds of natural polysaccharides (sodium alginate (SA), chitosan (CS), pullulan (PUL)). Layer-by-layer electrostatic deposition technique was used to prepare bilayer films composed of B1 containing SA layer and CS-PUL layer and B2 containing SA-PUL layer and CS-PUL layer. The films were characterized by Fourier transform infrared spectrum (FTIR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), and the water barrier property, mechanical property and light transmittance were investigated. The results showed that, compared with monolayer films, the peak of key groups in the FTIR of the bilayer films changed and shifted; the crystallinity changed; and the endothermic and exothermic peaks of the DSC curve shifted, indicating that the layers in the bilayer films were not simply superimposed, but subjected to some electrostatic interaction. Tensile strength of the bilayer films increased significantly and light transmittance decreased. In addition, elongation at break and water vapor permeability were between the corresponding monolayer films. Therefore, the bilayer film combines the advantages of each monolayer film, and has better physicochemical properties, which has certain advantages in the field of food preservation and packaging.