Abstract. For modeling the organizational form of business activities in complex production processes, a workflow model based on binary tree for process management in PDM is presented in this paper. Take use of binary tree structure, each business activity is organized by the relationship of parent-child and brotherhood as the node of the binary tree, simulating the organization form of the actual production process. With introductions of elementary structure unit, the binary tree node, including type, state and constraints, it illustrates scheduling algorithms of node and mechanisms of control patterns and state transition. Finally, with a simple project template case study, we can find that this model is easy to implement overall control of process and has a good adaptability to process changes.