Biopolymers are increasingly used in everyday life as a substitute for synthetic polymers due to their biodegradability as they have a significant impact on reduction of environment pollution and CO2 emissions. One of the widely used biopolymers is chitosan. Due to its extremely good properties such as biodegradability, biocompatibility and antimicrobial activity, chitosan is used in the food industry, biomedicine, and the coating industry. In this work, the films of pure chitosan (Cs) and chitosan with the addition of titanium dioxide (Cs-TiO2) were studied with the aim of increasing the effect of antimicrobial activity and reducing the adsorption of organic matter. Samples of chitosan films were prepared by dissolving high molecular weight chitosan (100.000 - 300.000 Da) in 1% acetic acid solution, and nanocomposite films were prepared with the addition of 5 wt. % titanium dioxide (TiO2) nanoparticles in chitosan solution. Characterization of chitosan films was performed by determining the antimicrobial activity on three bacterial cultures: Escherichia coli (3001), Pseudomonas aeruginosa (3011) and Bacillus subtilis (3020). Then, the contact angle was determined using a goniometer and the mechanical properties were determined by testing machine performing a stress - strain measurements. The morphology of chitosan films was characterized by scanning electron microscope (SEM) to determine the dispersion of nanoparticles in the chitosan matrix. Analysis of the results shows that the samples of chitosan and nanocomposites of chitosan do not have antimicrobial activity for any of the three tested bacterial cultures. The addition of TiO2 nanoparticles to chitosan resulted in a change in mechanical properties and a decrease in hydrophobicity.