Abstract: In order to minimize the coolant flow for transpiration cooling rocket nozzle with sintered porous media wall,an optimized transpiration cooling structure was presented in this paper,whose porous wall was divided into several sections along the axis direction.The transpiration cooling for a thruster with four-section structure porous wall was numerically studied by Fluent code and the results were compared with those of the one-section structure transpiration thruster.The results show that four-section structure can decrease the ratio of coolant flow and gas flow from 28.3% to 12.6% on the premise of satisfying the cooling need of the nozzle inner surface wall,the multi-section porous wall design is an effective way to reduce nozzle transpiration coolant flow.