Abstract: The technology for membrane fouling control and flux recovery is the key issue to improve the separation properties of the ceramic membrane and it can bring forth great economic benefits. Ultrasound cleaning technique was applied to the removal of fouling of ZrO2 ceramic microfiltration membrane，which was used to treat emulsification wastewater. The results showed that the effects of membrane cleaning were influenced by ultrasonic power，cleaning time and the level of membrane fouling. The flux recovery rate was increased by enhancing ultrasonic power provided condition that it was safe for the ceramic membrane. The suitable cleaning time was about 20 minutes. The water cleaning assisted with ultrasound was proved to be an effective way to clean membrane surface fouling which came from concentration polarization and gel layer on the membrane surface，but was less effective for membrane pore blocking. The chemical cleaning assisted with ultrasound could recover membrane flux effectively and shorten cleaning time.