In this paper,we present a technique for the collaboration among the members of computer generated actor team in the virtual environment. We research multi agent models in artificial intelligence and put our emphases on the structure of the team members. We analyze the hierachical relationship among team members in the real world and apply it to computer generated team. In this approach, we present a hierachical collaboration model based on the Planned Team Activity model. The hierachical relationship among the team members is organized as a hierachical tree and each member of the team maintains this relationship. To maintain the hireachical relationship, this paper also gives some atom rules and functions to adapt the dynamic environment. Using our improved model, the team can work effectively and dynamically in real time. The result shows that by using the hierachical model the collaboration among the team members in the virtual environment is improved.