Abstract: Scanning electron microscopy and ultrasonic treatment were used in the study on the effects of removal Listeria monocytogenes biofilms. The results showed that ultrasonic processing temperature,time and ultrasonic power had a positive increasing in the clearance of Listeria monocytogenes biofilms. The two- factor interaction analysis and partial regression equation coefficient analysis showed that the three factors affecting the clearance in a descending order as: ultrasonic processing power > time > temperature,and the optimization of ultrasonic treatment for: ultrasonic processing power was 250 W,temperature 35℃ and 7min time. The clearance rate of Listeria monocytogenes biofilms was 96.34% under the condition of the verification experiment.