Abstract: Due to the characteristics of flood in regions in North China, it is difficult to determine the flood prevention standard after dividing the whole flood season into sub-seasons. This study develops alternatives for the reservoir's limited water level in post-flood seasons through optimization based on the three angles:the flood prevention, flood utilization and the balance between them. A multilayer fuzzy optimal selection model is established by coordinating the complex relationship among the multi-objectives. The proposed method is applied to Biliuhe reservoir and raises the limited water level in post-flood seasons without decreasing the flood prevention standard. The results show that it can provide technical support for the decision-making and be applied to those reservoirs in the water shortage regions in North China.