Abstract: Ultrasound is widely used in food industry as an efficient processing method due to its low energy consumption and heat generation.Meanwhile, the negative effects of the sound chemistry caused by ultrasound in certain conditions need to be considered. This paper reviewed the positive and negative effects of ultrasound-assistant process on extraction of polyphenols, the mechanism of cavitation caused by ultrasound, the main factors influencing the cavitation, the pathway of the occurrence of hydroxyl radicals in aqueous liquid caused by cavitation, and effect of cavitation on the stability of polyphenols.