Abstract: Aiming at the problem of uncertain model and lack of automatic reason reasoning support in context-aware technique,the paper proposed an approach to model and reason the context-aware knowledge based on description logic．It suggests a context model framework in the semantic restrictions of the ontology,which divides the context model into two-level structure as meta ontology and domain-specific ontology,according to the abstract hierarchy．The objectives of our model framework include modeling a set of high-level entities,and providing flexible extensibility to add specific concepts in different application domains．After that,the paper proposed an algorithm to convert the context model to the knowledge described in description logic using SHOIN(D)．Finally,a case study was given to illustrate the practicality of the method．

Key words: Context model,Description logic,Ontology,Context reasoning