With the rapid development of modern cities, relatively backward traffic management methods, inadequate road planning and construction, and the surge in car ownership, the problem of “urban traffic congestion” has become a problem faced by modern urban management. Intelligent Transportation System (ITS) is gradually becoming the research direction for solving the problem of traffic congestion in various countries around the world. Based on the above background, the purpose of this article is to study the vehicle communication network in the intelligent transportation system based on the Internet of Things. This paper uses OPNET Modeler software to build a vehicle movement model. OPNET Modeler uses a layered network simulation method. From the perspective of the protocol, the node module complies with the OSI standard of the open system interconnection model. From bottom to top, it is the physical layer, MAC layer, ARP layer, IP encapsulation layer, IP layer, TCP layer, and service layer. In a multi-hop scenario of vehicle self-organizing network in an intelligent transportation system based on the Internet of Things, simulation experiments show that when the vehicle is running at low speed, the wireless network coverage problem of the vehicle self-organizing network on the ground, especially In terms of the design and configuration of the roadside unit, the distance of the roadside unit should be maintained between 500 m and 600 m. At this time, the overall performance of the vehicle self-organizing network is stable. AODV protocol is superior to DSR protocol in terms of throughput, average network delay, routing load, packet loss rate, and average routing hops, and is more suitable for network communication needs.