Abstract:Taking the runoff data of 23 meteorological stations in the Huaihe River Basin(HRB) from 1951 to 2016 and the runoff data of the Bengbu hydrological station as the research objects, linear quasi-legal, sliding average and non-parametric MK test were used to analyze the characteristics of precipitation and drought in the HRB.The correlation between precipitation, drought and runoff and long-range memory was analyzed with the combination of R/ S analysis, Pearson and Spearman correlation coefficient. The results show that except for continuous wet days, the extreme hydrological index of HRB showed a significant increasing trend, and the abrupt years were concentrated in the 1950s and early 1960s. In the past 70 years, the annual drought frequency reached 21.2%, and the proportion of light drought was the highest. From the annual and seasonal scales, the winter drought is the most severe, and the annual and seasonal drought show a decreasing trend. There is a moderate correlation between precipitation and runoff over a maximum of 30 and 15 days. The precipitation and runoff in flood season and non-flood season are moderate and weak respectively. In the next 4 to 11 years, the maximum 30-day precipitation and runoff, the precipitation and runoff in the flood season and the non-flood season willnot show significant growth trends.