A system using a Single Chip Micyoco(SCM) to test and control the speed of ultrasonic motor was studied.Based on the relation between the ultrasonic motor's speed and its driving frequency,the speed of ultrasonic motor working in vacuum is controlled by fuzzy PI control strategy.The test results prove that the ultrasonic motor using the system can work steadily in design speed in vacuum(the highest vacuum degree can be up to 0.003 Pa),and the speed deviation doesn't exceed 1 r/min.It can satisfy the requirement for measuring and controlling the speed of ultrasonic motor working in vacuum.