Aimed at solving the problem that management profits between the cooperation of owners and contractors are inefficient in the BOT+EPC large-scale model， this paper pro-posed the establishment of the owners and the contractor cooperation trust mechanism.Through the state variable， speed variable， auxiliary variables， constants four indexes of causality diagram and system flowchart to establish a system dynamics model and simula-tion system， the simulation analysis shows that the owner and the contractor.The simula-tion results show that the cooperation trust mechanism can make their mutual induction trust， motivation based on excitation of both， to enhance management efficiency.