In this paper, the comparative experiments were carried out to investigate the output characteristics of two different ultrasonic motor prototypes (type A and type B) using a longitudinaltorsional vibration converter with multiple diagonal slits. The rotational speed was measured by a laser tachometer. The effects of operating frequency, driving voltage and prepressure on the rotational speed the two prototypes are analyzed. The results indicate that the structure of multiple diagonal slits has obvious influence on the output speed. The maximum revolution speed of the prototype (type A) is 87 r/min and the maximum revolution speed of the prototype (type B) is 135 r/min with the same resonant frequency of 37.7 kHz at the conditions of input voltage of 100 V and rotational speed of 0.21 N.