The lack of protein in the diet of humans and animals, the presence of a large amount of plant waste, which have further potential for use, but are now almost not used, are serious problems that require immediate solutions. Modern methods of biotechnology are able to solve this issue. The purpose of this review was to study the existing technologies for using yeast to produce protein from plant waste. Waste of plant biomass, which are initially indigestible polysaccharides, when using special processing methods, break down into easily fermentable sugars, which can serve as a good substrate for the accumulation of full-fledged yeast protein, and the yeast cell wall is able to bind toxins, undesirable microorganisms and remove them from the intestinal tract of humans and animals, allowing them to be included in the composition of biologically active additives for functional purposes. The review examines the advantages of using yeast in comparison with other microorganisms and the technology of the process. It is possible to use deep and solid-phase cultivation, the first of which is technologically preferable. The products and preparations produced by foreign and domestic manufacturers are considered. Yeast is used for feed preparations:Candida, Saccharomyces, Hansenula, Torulopsis, Rhodotorula, etc.; for the food industry – mainlySaccharomices cerevisiae, Torula. The resulting products, enriched with protein and components of yeast cells, differ significantly from analogues in nutritional value. This approach to the use of industrial waste at enterprises can make many production cycles closed, increase the environmental friendliness of plants, reduce unnecessary waste disposal costs and increase total revenue.