Direct memory access(DMA)is an important technology used for fast speed data transfer in data signal processor(DSP). DMA is able to move data block independent of CPU, and this capability meets real time image processing. TMS320C6201 DSP is taken as an example, and DMA controller characteristic is introduced. According to DMA application in realtime image processing, the specific control ways and realization steps are given out. The research result shows that the flexible control DMA can not only raise image data transfer efficiency but also improve DSP speed.