C4ISR(command control communications computers intelligence surveillance and reconnaissance)/Sim(simulation) integrated system developed under service-oriented architecture(SOA) can use same information acquiring methods and information representation syntax. Semantics-oriented C4ISR/Sim integrated system proposed is to extend SOA by hierarchical semantic structure, which was improved in flexibility, reusability and expansibility of system construction as well as semantic interoperability of integrated system. Based on domain ontological model in core service layer, the architecture expanded semantic description of model service in domain-specific service layer. Using semantic service matching, it realized automatic mapping between requiring description in application layer and the composition of system. Realization of prototype system proves that its design method is correct and applicable.