Aiming at the prevalent problem, information silos, in the transportation information system, as well as data security, authentication in network data transmission and other issues, a generic Web Service-based traffic data exchange method is proposed, which consists of formatted data exchange packet and service interface invocation. Among the method proposed, the data exchange packet is to standardize data, while the service interface invocation is to achieve data exchange process standardization. With the help of the example of data exchange in "Vessel based information collection and exchange interface specification", which gives xml format packet and the Web service interface, it shows that the proposed method can not only improve the inadequate of data exchange method and business logic associated with weak in the information system of transportation industry, but also improve the security of data exchange.