Aimed at a series of problems existed in the traditional biomass pelleting technology, such as needing of high temperature, high pressure, and the pollution resulting from additional additives, a dual ultrasonic pelleting technology of biomass was presented, and a pelleting machining tool was developed. A detailed design of ultrasonic vibration system was carried out, and its rationality of the design was verified through simulation analysis and experiments. The technics experimental results demonstrated the high performance of the dual ultrasonic pelleting biomass system. The results show that the thickness of the pellets with ultrasonic vibration process is effectively decreased, and the density of the pellets is increased. Moreover along with ultrasonic power increasing, the thickness of pellets is reduced, and density is increased.