Abstract: Importance of Intelligent Transportation System(ITS) and its trend are discussed. The networking architecture of ITS is put forwarded and analyzed. Then, the middleware used in ITS is touched on and its key place in ITS is also pointed out. After the design of the intelligent transportation system message queuing middleware(ITS-MQ), its constructs and components are illustrated. Then, this paper focus on the analysis of the process of ITS-MQ and then its features are also refereed. In order to verify and formalize the protocol used in ITS-MQ, we adopt the Colored Petri Net(CPN) to describe it. And the result shows that this technology is very useful to do this. The result also proves that ITS-MQ middleware is applicable for ITS.