Abstract: Based on the analysis of the muscle and skeleton structure as well as the neuromuscular control mechanism of labriform pectoral fin, a new under-actuated bionic pectoral fin is designed, and the structure, function and parameters of this bionic pectoral fin are described. Then, a distributed real-time measurement and control system is designed for this device based on CAN (controller area network) bus. Meanwhile, the structure and function of hardware and software of this system are analyzed in detail. At last, a prototype of bionic system of pectoral fin is manufactured, and the feasibility and validity of this new bionic system of pectoral fin are proven by experiment in simulating the propulsion motion of real pectoral fin.