BIM ( Building Information Modeling) system is still in the initial stage of development in China,and it has its different data organization and software system in each period of the life cycle of modern building. This makes it more difficult to build a unified information system. How to integrate the effective data,and reflect the architectural information effectively becomes one of the key points of the researches on BIM system. In order to solve the problem of sharing information,applying the field knowledge and making BIM more intelligent,ontology technology was proposed which could be constructed by the standards and experiential knowledge. In this paper,the ontology-based application framework of BIM was proposed,and the way that puts domain ontology into the BIM system was also given. A variety of personalized services can be provided through the combination of the domain ontology and the existing knowledge and data.