A new model is presented based on combined guide curves for optimizing hydropower production and for better storage distribution among cascade reservoirs. The model is optimized with the particle swarm optimization algorithm and storage distribution among cascade reservoirs is achieved by the storage effectiveness index method. The model is applied to the Qingjiang cascade hydropower plants and optimized combined reservoir operation chart is obtained for Shuibuya- Geheyan reservoirs. Comparing with the current design, the proposed model is capable to produce an extra amount of 201 GWh electrical energy (a 2.77% increment) and save 1067 Mm 3 of flood water resources (a 38.96% reduction) annually.