With the quick urbanization and development of industry,the ecology and environment in cities are subjected to the extremely serious threat leaded by the more and more increasing production of sludge. In order to effectively eliminate such environmental pollution as the sludge, and promote its utilization, an advice of application of ultrasound technique in sludge treatment is put forward. Based on the present status about domestic and foreign study of ultrasonic treatment of sludge,three main advantages of ultrasound technique are concluded,such as disinfect pathogens, deodorizing, sludge stabilization improving and remarkable dewatering,increase of the nitrogen and phosphorus content in sludge for its much better utilization. In addition, the present problems needed to be solved urgently for this technique in our country are pointed out,as the directions and keys for the further study of ultrasonic treatment of sludge.