The aim of the study was to assess the potential of organic wastes from the agriculture and food industry as co-substrate for biogas production, on the basis of physical and chemical parameters analysis and biogas yield in the process of methane fermentation. The experimental material consisted of carrot pomace, kale by-products and maize silage. Methane fermentation was conducted in bioreactors equipped with an automatic control and measurement system. The study indicated correct physicochemical properties in terms of high content of dry organic matter and also correct C/N ratio. That was reflected in high biogas yields which amounted to, respectively, 558 N dm³ kg^-1 VS^-1 for carrot pomace and kale by-products, and 526 N dm³ kg^-1 VS^-1 for maize silage. The study showed that the intensity of biogas production was varied and depended on the composition of fermented mixtures. Methane fermentation of organic waste mixtures significantly increased the amount of biogas efficiency compared to the fermentation of individual substrates. The successful run of the experiment indicates that a mixture composed of carrot pomace and kale by-products is a good substrate for the production of biogas.