In order to detect the target position real-timely, a real time target detecting system based on tms320F2812 DSP and Spartan3-SC3S400 FPGA is designed. The design, hardware structure, a target detecting method and software char flow of FPGA and DSP are presented. The system is tested by a 1K×1K image, the processing time is 1.3ms, experiments results show that the method is feasible, the simple design and stable correct results make this method very ascendant in practical application.