Abstract: An optimal operation model with an objective of minimizing flood peak discharge at a protected location and with a series of constrains related to water balance of reservoirs and channel routing equations is established based on the analysis of the relationship between releases of reservoirs in parallel and flood peak discharge in protected regions. The solution of the model is reached by combining recursive multistage dynamic programming with practical flood regulation rule of "releasing, storing, and diversing in succession". A case study shows the flexibility, computational efficiency, and effectiveness of the method in preventing flood peaks from reservoirs and uncontroled area from meeting together in protected region. The methodology can be adopted in real time regulating of flood and planning of flood control system.