Abstract: If everyone or a unit in a team is assigned to specific work, the cooperation between teammates will be much easier than that without specific assignments. Nonetheless, due to the complexity of data coupling and space-time, the assignments with conflict constraints are a big challenge. As one of the most important but intractable constraints, the preorder constraint determines the prerequisites of assignments. Therefore, roles are introduced to abstract and model the assignment problem and express the assignment with the preorder constraints. Tested by the exhaustive method, the complexity of the proposed problem is of Σ2P. In order to optimize the solution of the problem and accelerate the processing speed, a multiple objective linear programming approach is proposed with the application of IMB ILOG CPLEX. To verify the proposed approach, simulation experiments are conducted. The optimization rate of the proposed approach could reach 80% to 100%, average 94%, which can meet the requirements of solving a certain number of problems within limited time as well as guarantee an excellent team performance and hence help support collaboration and management effectively.