Abstract: The arithmetic of beamspace MUSIC (BMUSUC) is the most representative method of beamspace high-resolution direction-of-arrival (DOA). It plays an important role in underwater object detection and tracking system. ADSP-21160, which is developed by ADI, is a high performance DSP with good properties of parallel processing and high-speed. On the platform of parallel signal processing system with multi-processor，which is composed of 4 ADSP-21160s，the effective system architecture and the method for data processing are used to reduce operation count and to improve parallel processing efficiency. As a result, the arithmetic of beamspace high-resolution DOA can be realized real-timely to satisfied the engineering technique requirement.