With the fast development of the transportation and navigation technology, the application of multimodal route planning is becoming popular. The routing systems and services are evolving from mono-modal to multimodal. However, it is difficult to apply the traditional data models and algorithms directly to the multimodal situation. A reasonable data model must take the multimodal application background into account, which is considered the critical foundation of the multimodal route planning solution. For the purpose of building such a model, we propose a concept named Switch Point, and a multimodal network model which consists of three components: multimodal graph set, vertices attributes table and switch point matrix. The experiments conducted on the real urban transportation road networks showed the feasibility of our proposed model. Our work can provide a foundation to support the study on multimodal route planning algorithms both theoretically and practically.