With the continuous improvement of expressway mileage, traffic volume and traffic speed, the interference and influence range of road traffic noise pollution on the normal life, work, study and rest environment of residents along the expressway are also intensifying and expanding. Road traffic noise pollution has gradually become an environmental problem concerned by the population in the basin. In particular, the traffic noise of main roads in some large and medium-sized cities exceeds the standard seriously, which seriously affects the urban residents and commercial activities on both sides of the road. This paper takes Wangdingdi main road overpass as the monitoring object. The overpass is located in the main road, with long running time and overweight vehicles, and the traffic noise generated by it has caused great harm to urban traffic. Through the noise monitoring of its two main roads, the present situation of noise pollution is summarized and its future development trend is predicted. Through the research of this paper, it provides a favorable basis for the monitoring and management of traffic noise on the overflow road of Guandi in the future, and provides favorable conditions for the future urban traffic construction. How to prevent and control noise in trunk line is of great value in practical application.