Abstract : Coloured Petri Nets (CPNs) have formal semantics and can describe any type of workflow system, behavioral and syntax wise simultaneously. They are widely studied and successfully applied in modelling of workflows and workflow systems. There is an inherent problem regarding business processes modelled with CPNs sharing and subsequently their reuse need to be considered. The Semantic Web technologies, such as ontologies, with their characteristics demonstrate that they can play an important role in this scenario. In this paper, we propose an ontological approach for representing business models in a meta-knowledge base. Firstly, the CPN ontology is defined to represent CPNs with OWL DL. Secondly, we introduce four basic types of manipulation operations on process models used to develop and modify business workflow patterns. To the best of our knowledge, representing business process definitions and business workflow patterns as knowledge based upon ontologies is a novel approach.