Abstract: To minimize the negative impact of overtime working, a new multiobjective optimization model is put forward and the corresponding solution algorithm is proposed. First, a feasible overtime work set is generated for each activity in the initialization stage. Then, the project duration, human resource cost, and total overtime hours of each scheduling plan are calculated by using the scheduling module. Finally, with a multiobjective genetic algorithm module, a Pareto multiobjective solution set is obtained. In addition, this algorithm is used in a case study, and the results show that the model is good in practicability, and can provide decision support for project managers on overtime scheduling.