The search for a rational design of an animal feed mixer is reduced to determining the structural and operational parameters of a machine that, in terms of its quality and energy costs, would most fully meet the zootechnical and technical and economic requirements. The analysis of the most typical designs of feed mixers was made. Their main shortcomings were revealed: low productivity, complexity of hardware solutions of the main processes, high energy consumption of the mixing unit and the probability of jamming when objects hit the sides; lack of control over the mixing parameters; complexity of the process of unloading the finished product and its automation; manual control of nodes. The classification of feed mixers is proposed according to the indicators of the greatest influence on the quality of the mixture and the energy consumption of the process: the type of feed; kinematic mode; the nature of mixing; the constructive sign; the design of the hopper; the number of mixing shafts; the location of the working body; the method of mixing; by the type of movement of the components being mixed; by the type of working body. A promising design was chosen: according to the type of feed – for dry; according to the kinematic mode - slow–speed; by the nature of mixing – periodic action; by the structural feature - with a fixed body; by the design of the hopper – round shape; by the number of mixing shafts – two–shaft; by the location of the working body – inclined; by the method of mixing – forced action; by the type of movement of the components being mixed - circulating; by the type of working body – screw with an active reverse channel. The use of such a design will ensure high quality of mixing; will increase the technological reliability of the mixing units; it will reduce the specific energy costs for the process of preparing a portion of the lump mixture.