Based on grade data of drought and flood of Anhui for recent 554 years,the statistic analysis are made. The results show that the series are partial distribution,or floods are more than droughts,and the series have the feature of periodic variation,and the series also have the alternation between drought and flood. That turning points appeared in about 1723,1774 and 1913,that were tested by the analysis with moving-t method and Yamamoto method.