Technical field: the invention relates to the field of agriculture, and more particularly to the production of feeds from non-fodder raw material, specifically waste from the rice processing industry. Aim: to expand the range of raw materials for producing feeds for farm animals, in particular cattle, and to produce a nutritious feed from secondary resources from the rice processing industry not hitherto used for this purpose, which can be used as a complete feed and also as a novel ingredient in the production of compound feed for cattle. Essence of the invention: a method is proposed for producing feeds from rice processing industry waste, which involves grinding a plant matter and subjecting same to biofermentation treatment using an active culture of Trichoderma lignorum, wherein the main plant matter used is rice hulls and rice flour, which is ground to 0.2-0.5 mm and then hydrothermally treated at a temperature of 110-120°C to a moisture content of 50-60% at a pressure of 1-2 atm for 1.5-2 hours, whereupon a biofermentation mass ("Trichoderma lignorum 19") is added to the plant matter in an amount of 5-15% of the mass of the raw material undergoing processing, the mixture is directed to a sealed bin for implementation of a microbiological process of impregnation and build-up of protein mass for 24-48 hours, then the resulting biomass is dried at a temperature of 50-60°C to 13-14.5% moisture content to produce a finished product.