Abstract. Tbe society is entering into knowledge-based economy, managing experience knowledge effectively is more important. Process-oriented knowledge management aims is the integration of business process and knowledge management, in order to solve the problem of process knowlcdge exchange and sharing in enterprise or between enterprises, an ontology-based approach to modeling and integrating enterprise process knowledge was proposed and an Enterprise Process Ontology (EPOnt) was developcd. Hs fundamental information is represented by the IDEF5 language graphically based on the reasons that most of ontologies have formal semantics but lack of graphical representation currently. Moreover, its precise syntax and formal scmantics are defmed in the Ontolingua language characterized by traits such as stronger expressiveness and compatibility with multiple representation languages and systems. Based on those, an actual Guangzhou Port Group business case was illustrated to show the application of the EPOnt and the architecture of an EPOnt-based enterprise knowledge integration management platform was presented. Tbe proposed approach provides a common understanding of a relevant vocabulary of terms and enhances the semantic interoperability, reuse and share of process knowledge for improving server efficiency and quality of enterprise.