In the Mid-May of 2015, the middle and downstream area of MeiJiang River Basin encountered a rare flood, which caused a heavy damage and loss of property. Analysis on the precipitation and runoff after the disaster finds the flood with return period of 50 years at MeiJiang River control station and the rainstorm of 300-year return period at Miao Zitang station in the middle reaches. The characteristic of this rainstorm flood is analyzed, which provides the guidance for disaster reduction and flood forecasting in MeiJiang River Basin.