Power ultrasonic honing has been proved to be a complex vibration system, grindering chatter may be generated during power machining process, and many different influence factors can cause the chatter such as physical grinding process, mechanical vibration, high frequency vibration and ultrasonic transmission system. The dynamic model of chatter of power ultrasonic honing was established. The influence of acoustic pressure radiated by collapsing cavitation on the regenerative chatter was researched mainly. The results show that the main cause of the regenerative chatter of power ultrasonic honing is the thickness of the grinding; the acoustic pressure radiated by collapsing cavitation can increase the frequency of chatter of the system, but no obvious effects on the change trends of time domain and amplitude of the system.