Abstract: The article perform a on-chip prefetch memory system for stream processor to solve the problem that memory access can not match the processor in the high-performance VLIW DSP. The prefetch memory system can prefetch the data and read or write correctly. It contains the stream prefetch control and memory's state transformation. The article assess the area and performance of the design, the result proves that using the prefetch memory system, it only increases little areas and the performance of the stream processor can improve about 14.6% than without it.