To manufacture rapid metal tools ，an innovative method based on rapid prototyping and high pressure spraying technologies is proposed in this study.The Sn-Bi meral alloy with low melting point and small thermal shrink was used as the spraying materials. Applying an electric heated device and high pressure boost pump. the melting Sn-Bi Alloy wentt through a small spray nozzle and atomized into semi-melting minute particles.The atomized particles are then deposited and integrated on the surface of intermediate silicone rubber mold. which is made from the rapid prototyping(RP) system and are successfully used to manufacture rapid was injection mould.Using the thermal spraying system to manufacture rapid metal mold，the surface quality and the dimensional accuracy of the spray mold is excellent and the fabricated cycle time is short. Keywords:Rapid Tooling ，Sn-Bi Alloy Spray.