Real-time target tracking on upper computer using CPU will spend much time because of a great amount of calculation，which will affect the tracking. In recent years, nVidia Corporation has put forward a compute architecture called Compute Unified Device Architecture(CUDA) which calculates in parallel using Graphics Processing Units(GPU). This study introduced the architecture and principle of CUDA, then tracked target in real time using this method, and compared the calculating speed of CUDA with that of traditional method. The result showed that CUDA could speed up calculation and be well used in real-time target tracking on upper computer.