Abstract: In order to reduce the labor intensity of small (light) truck when loading bulk materials, a small loader with foldable hopper was designed. The overall design scheme is：The hopper is open in heavy section and has the largest loading capacity and the hopper is folded in the return section, which effectively saves the space under the frame and reduces the height of the machine. The physical and mathematical models of hopper are set up. The optimum angle of the frame and the hopper opening angle is determined 60° by using MATLAB, so that the loading capacity of the machine reaches at least 12.5m3/h .The shape and position parameters of the guideway are designed to ensure the opening and folding of the hopper. The trajectory of the hopper in the loading section is simulated by Pro/E. The simulation results show that the hopper can automatically load during the process from folding to opening.