Abstract: The development of complex mechanical products have the characteristics of knowledge intensive,knowledge reuse plays an important role in the development.Researched on the easily ignored process knowledge in the whole life cycle of mechanical products,buildging process knowledge ontology based on the whole life cycle and structure of the product,to refined the large-grained ontology to knowledge tree which contains knowledge nodes and knowledge points.making the design process knowledge to a model which is corresponded to knowledge tree,then reuse the whole life cycle design process knowledge by knowledge tree navigation and keywords retrieve which meet the needs of different level of developer.Taking the grab for example,developed the process knowledge reuse system of the whole life cycle based on knowledge tree navigation,prove that the method is validated.

Key words: process knowledge, knowledge modeling, knowledge reuse, knowledge tree navigation, keywords retrieve