Abstract: The incremental evolving process of a product under virtual development is represented by a tree-like-model named virtual prototyping tree. Design teams with different majors work together around the tree to materialize the conceptual design and improve its performance progressively in a spiral way.Such an approach can avoid the long lasting try-and-error process of product development and highly effectively utilize the joint efforts of teams. The concurrent design environment established in such a way has been verified successfully in a real project.