Among plastic products, food packaging is used for the shortest period of time because it is determined by the food shelf life. With perishable foods and products meant for immediate consumption, it can be used for even less than one day. After use, this plastic packaging becomes waste, which can be recycled, ends up in landfills, in incinerators or in the environment. Many studies are focused on finding an alternative packaging, and one of the proposed possibilities are chitosan-based films with various natural extracts that improve antioxidative, mechanical and antimicrobial properties and enhance barrier properties (UV protection, CO2, O2 and water). Because of their potential biodegradability, biopolymer-based films are a promising alternative to conventional plastic. In the master’s thesis, I studied the biodegradability of chitosan-based films with added oak extract in three different types of soil: compost, soil for gardening and soil from vineyards. Degradability was tracked through mass loss, change in polyphenolic content, FT-IR analysis and by examination of surface using a scanning electron microscope. The impact of increased soil humidity was also evaluated. The results have shown that chitosan-based films with no added extract are biodegradable in all types of soil and at both tested water contents. Films with added oak extracts were completely biodegradable in compost and gardening soil, but not in vineyard soil. It was also discovered that adding water to soil slowed down the rate of film degradation.