Abstract: In order to analyze the distribution of soil pressure on dump truck cargo body, based on the sliding plane hypothesis of coulumb earth pressure theory, the calculation formulas of active soil pressure acting on each plate of cargo body were deduced by using the thin layer element method, considering the complicated circumstances that the soil material was soil with cohesion and friction angle, the frictional and adhesive forces existed between soil material and cargo body and road slope. The distribution of soil pressure acting on each plate of cargo body was analyzed when cargo body was loaded sand and clay. The results indicated soil pressure acting on the rear plate and side plates had nonlinear variation, while on the front and the rear part of the bottom plate had linear variation. The soil pressure acting on the middle part of bottom plate was unchanged. The soil pressure on rear and bottom plates when vehicles ran on a road with 30% slope was both greater than flat road, while the soil pressure of side plate changed a little. The value of soil pressure on the rear plate was obviously greater than that was calculated by classical Rankine. When the truck was loaded dry coarse sand, dry fine sand, wet coarse sand, wet fine sand, the value of soil pressure increased by 255%, 174%, 310% and 255%. When the truck was loaded wet clay and medium clay, the value of soil pressure increased by 11% and 107%。The deduced calculation formula of active soil pressure acting on each plate of cargo body will provide scientific reference for structure design and performance analysis of dump truck.