Facing the varying demand for digital signal processing applications, the existing solution including general-purpose processor, DSP, ASIC and FPGA can not meet the requirements of cost, power consumption, performance and flexibility. To solve these problems, this study combined the technologies of stream processing, and reconfigurable platform, and proposed A Multi-Granularity Reconfigurable DSP based on Stream Architecture Template (MGR-SAT). MGR-SAT uses stream processing techniques to decouple the data on operations and memory access, offering a large-scale data parallel. Meanwhile it uses the reconfigurable technology to accelerate the key algorithms and uses the platform technology to provide fast reconfiguration as well. The experimental results show that MGR-SAT has a great potential to deliver high performance.