In this study, a PWM technique is presented for digital signal processor controlled drive system of travelling-wave ultrasonic motor. The drive system is high-frequency two-phase serial-resonant inverter using mechanical resonant frequency of the ultrasonic motor. A TMS320F243 digital signal processor was used to control ultrasonic motor drive system. PWM signal was generated and then applied to the low pass filter to produce reference DC voltage level for speed control of ultrasonic motor. The driving frequency was selected as control input in the speed and position control loops. Experimental results show that the proposed drive and control system gives superior steady-state and transient performances in the speed and position control of ultrasonic motor.