Abstract: The paper proposed a design scheme of communication interface between ARM and DSP based on dual port RAM. The interface takes ARM as main processor and DSP as coprocessor. ARM is used to realize management and dispatching work of DSP tasks through tasks management thread of DSP built on Linux system, and DSP is used to realize data calculation and processing work sent by ARM. The both exchange data through dual-port RAM. The actual application showed that the interface fully uses function characteristics of the two processors with quick data transmission speed, which is suitable for situation with the need for large acounts of data exchange between ARM and DSP.