Ultrasonic Motor (USM) is a new type of micro motor, it has excellent characteristics.With the rapid development, it has broad prospects of application in the field of non-continuous movement and precision motion control.The driving system is very important to the performance of the motor.This article describes the design of a drive power.It has a simple structure, easy to operate and a low cost.The microcontroller AT89C51 controller generates high-frequency PWM signal, the power amplifying unit for power supply of the ultrasonic motor (USM) through the phase shifting unit.Each module unit is designed carefully.It has been proved that the system meets the design specifications after the systems debug and analysis.