Abstract: Considering the technology background and the structure characteristic of superscalar processor, novel mapping method was studied to implement the FFT effectively. Firstly, the structure of modern superscalar processor was modeled, and then the effect of FFT implementation on the processor was analyzed. The analysis results show that the EMS memory accessing is the key point of FFT algorithm implementation. Further more, the accessing process of FFT processing was modeled to implement FFT mapping effectively based on cache optimization. The new mapping method splits sequence of FFT into short sequence to exert the function of cache sufficiently. Finally, a radix-2 FFT was implemented on the ADI's TS201 digital signal processor based on the new mapping method. The result shows that the implementation time of FFT is improved greatly.