Abstract: The Virtual assembly process planning in virtual environment is researched. The integrated system architecture is analyzed. The three main problem of virtual assembly planning: virtual assembly, assembly sequence planning and assembly path planning are analyzed. A product assembly model in assembly process planning is put forward, and the method of how to identify assembly constraint relations in the virtual environment is proposed, then method to constrain components’ 3D spatial movement under the constraint relations is realized. Based on these, a prototype system is established. Thus, a good background for the further research of Virtual assembly planning is established.

Key words: Assembly process planning, Product assembly model, Virtual assembly, Virtual reality