This paper introduces an approach to OWL-based hybrid product knowledge model for collaborative engineering environment. The participants in collaborative engineering want to share and reason product knowledge through internet without any heterogeneity and ambiguity. In this paper, the hybrid product knowledge model is proposed using first-order logic(FOL), relational database(RDB) and web ontology language(OWL) according to a formal ontology. Our knowledge model can be used to develop an integrated knowledge-base which reduces heterogeneity and ambiguity. Firstly, the collaborative engineering domain is analyzed and then the product knowledge is organized into four levels such as product context model, product specific model, product design model and product manufacturing model. Secondly, the four levels are represented by FOL in layered fashion. The concepts and the instances of a formal ontology are used for recursive representation of the four levels. The instances of the concepts of an upper level like product context model are considered as the concepts of an adjacent lower level like product specific model, and this mechanism is applied to the other levels. Thirdly, these logic representations are integrated with the schema and the instances of a relational database. Finally, OWL-based product knowledge model is developed, in which OWL representation of the four levels are defined through the integration of the logic representation and OWL primitives. Thus, a hybrid product knowledge model is constructed, in which the four product knowledge models have their major representation such as FOL, RDB, or OWL according to the characteristics of each model. This approach enables engineer to share product knowledge through internet reducing ambiguity, and utilize it as basis for additional reasoning.