Chitosan is a natural linear polysaccharide with some antioxidant and antibacterial properties, which has been used in a broad range of biomedical applications. In the present work, for the enhancement of its antioxidant/antibacterial activity a series of novel composite films, based on chitosan (Ch), hydroxyethyl cellulose (HEC) and natural antioxidant (bactericide) Enoxil, were prepared and characterized by atomic-force microscopy (AFM), dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). The AFM images of topography, profilograms and 3D images of free and contacting with substrate surfaces of composite films show that these films exhibit heterogeneous morphology and various nanoporosity depending on their composition and way of preparation. It was showed that introducing Enoxil in concentrations from 1 to 5.0 wt.% into Ch solution affected the morphology of the films - sizes of nanodomains and roughness of the free sample surface, as well as nanoporosity of the films. These changes can be explained by nanostructurization occurring due to the complex formation between the Ch and Enoxil. For the ternary composition, containing 2.5 wt.% Enoxil and 30 wt.% HEC, morphology of both surfaces of films looked like that of the initial Ch film; this can be explained by decreasing of interaction between Ch and Enoxil. DSC and DMA display that Enoxil introduction changes substantially the thermal, relaxation and elastic properties of composite films, and the behavior of materials under study depends strongly on the degree of their hydration. For initial hydrated Ch and Ch/Enoxil films (scan 1 with water desorption up to 1300C), the pronounced glass transition relaxation peak and dropping storage modulus by an order of magnitude are observed at 35-45°C. Meantime, water-free films display at scan II a step-like "unfreezing" mobility over the temperature range from ~ 50 to 250°C, with the most intense relaxation peak at 220-250°C and, then, the onset of exothermic process of thermo-oxidative degradation at higher temperatures. Some changes in the relaxation behavior of Ch in Ch/Enoxil and Ch/HEC/Enoxil films and the essential dynamic heterogeneity may be seen from both DSC and DMA data. Relaxation behavior and elastic properties indicate some structural loosening after introducing Enoxil and some suppression of molecular mobility at moderate temperatures due to HEC addition. . The increased antimicrobial properties of these biocomposite films have been shown in vitro and in vivo research for their use as valuable wound coatings films for healing of open skin traumas.