Abstract: In this study, design flood recheck is made by use of storm data, rainstorm chart and other methods in order to provide evidence for risk-elimination program and reinforcement measures for the Yandang reservoir. After an analysis of rain storm characteristics and rain storm frequency, by using the calculation results of the design point storm, the design rainfall pattern and the design surface rain storm, the runoff is checked with the deduction loss method. And then the convergence check analysis is made by the instantaneous unit hydrograph method, and the design flood for the risk-elimination and reinforcement of this reservoir is determined. Comparison with the results of the original design flood and other reservoirs near the Yandang reservoir shows that the flood recheck results are more reasonable. Now, the Yandang reservoir has withstood the test of floods since the completion of the risk elimination and reinforcement project and has been put into operation for three years.