In order to help Guangzhou solve the problem of highway traffic congestion, this paper investigates the real-time road conditions of highway traffic in Guangzhou in October 2017, September 2019 and May 2021 with the help of “Internet of vehicles” technology, and uses GIS technology combined with survey data to map the changes of highway traffic congestion in Guangzhou. At the same time, it also summarizes the new traffic congestion sections, the sections with the fastest increase in traffic congestion and the sections with improved traffic congestion in Guangzhou from 2017 to 2021. By further analyzing the reasons for the improvement of traffic congestion, this paper obtains the countermeasures that really take effect in the work of traffic congestion control in Guangzhou, and further puts forward some suggestions for traffic congestion control in Guangzhou.