After a brief introduction of the software radio technique used in spacecrafts and satellites, an architecture of a Spaceborne Software Radio Platform （SSRP） is given. The Single Event Effects （SEEs） for the SSRP＇ reliability is presented and a novel method is listed for the simulation and evaluation of SSRP＇ reliability design technology. As the main components of the SSRP Field Programmable Gate Array （FPGA） and Digital Signal Processor＇s （DSP） SEEs and reliability are even important, A fault injection method is listed for the simulation of SEEs and is introduced for the evaluation of the FPGA and DSP＇s reliability design. The design idea and fault injection method has the advantage of cheap and flexible and it has been adopted in a spaceborne multiuser receiver based on direct sequence spread spectrum technology and proved to be effective in the environmental test. With the reliability design method, low grade with high performance device is possible to be used in space.