Abstract: A large-load ultrasonic vibration grinding system is designed.It is composed of a transducer,a cylindrical conical horn and a spoke-type grinding wheel.Firstly,the spoke-type grinding wheel is equivalent to a composite model that the hub is cylindrical rod,the spoke and the rim are medium-thick plate.Secondly,the frequency equation of the system is deduced by the continuous boundary conditions of each contact surface,the ultrasonic grinding system design is completed,the experimental device is also manufactured,and the acoustic vibration characteristics of the device is analyzed and verified.The experimental results show that the spoke-type compound model utilized to obtain the system frequency equation is effective for solving the design problem of the large-load ultrasonic vibration grinding system.The ultrasonic system has simple structure,stable acoustic vibration characteristics,uniform displacement amplitude output.It is expected to be applied in the field of large-load ultrasonic grinding.