A Workflow process is a support for business activities and it is necessary to take into account the knowledge context of these activities. Use of ontologies is one the ways to consider this kind of knowledge. In this paper, we present an approach to build an OWL ontology Workflow. We firstly define a common Workflow meta-model using Meta-Object-Facility (MOF). It gathers all the common concepts that are generic and shared by the most Workflow models and it defines their semantics. These concepts (activity, resource, etc.) are extracted from different formalisms used in the field of business process (or Workflow). Then, we translated it into an Ontology Definition Meta-model (ODM) based on MOF and use the main OWL concepts and subsequently, from ODM to OWL meta-model which is also a MOF-compliant and is based on the Web Ontology Language (OWL). Finally, we mainly focus on OWL DL (Description language) that provides the leading ontological tool Protégé OWL Plugin for the generation of our OWL ontology Workflow.