The Description Logic, which possesses strong knowledge representation and reasoning capabilities, is the logic basis of the Semantic Web ontology languages such as OWL and OWL-S. The AJ planning, which provides an effective method for solving the planning problem and task decomposition in AI, possesses better modeling capability of the action state transformation. Based on the merits of the Description Logic and the AI planning above, this paper proposes a service composition mechanism
and testifies its feasibility in Description Logic. The results show that this composition mechanism can not only be feasible but also be hepful for the semantic modeling of the service composite process in the Semantic Web.