The utility model relates to a material return and powder supply device of a plant pulverizer. The material return and powder supply device comprises an outer shell and a main shaft mounted in the outer shell, wherein a cutter for pulverizing a plant is arranged on the main shaft; the material return and powder supply device is characterized in that a conical part for discharging powder and returning particles is arranged at an outlet in one side of the shell; reverse pushing blades are arranged on the main shaft and are positioned at the conical part. The material return and powder supply device of the plant pulverizer has the beneficial effects that 1, by the use of the reverse pushing blades and the conical part, automatic separation of the powder and the particles is realized, and the particles are turned into the outer shell for re-pulverizing; 2, a material discharging cavity is used for collecting and gathering the powder, so that material discharging blades can conveniently output the powder from a material discharging pipe; 3, the reverse pushing blades and a pushing block are of a separable structure, so that replacement is convenient, and components such as the main shaft do not need to be assembled and disassembled; therefore, the phenomenon that the cutter is easily damaged by the influence of assembling and disassembling of the main shaft on the position of the axis is avoided.