In order to solve the problem that current cloud manufacturing is still lack of application mode, a five-layer architecture of cloud manufacturing (CM) system based on Agent is proposed according to the characteristics of life cycle intelligent manufacturing, required dynamic gathering, and services of different granularities in CM. Based on the service-oriented ideology, a web ontology language for services (OWL-S) of CM is proposed to realize service requirement, release, and binding,based on ontology mapping, inference engine and matching box. An expanded framework for OWL-S and semantization description for CM services is put forward, providing the theoretic foundation of match for CM services. The consult mechanism for CM services is built to realize the dynamic gathering and operation by the cooperation, competition and consult of Agents. By analyzing the activity of complex, nonlinear and obvious dynamic CM system, the paper presents the IDEF0 view of CM system based on Agent and the operational mode of CM system is analyzed.