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Using the daily precipitation data of rainy season （June to August） from 1961 to 2008 of 117 stations over the Huaihe River Basin， the extreme precipitation thresholds are determined for different stations by means of the percentile method， and then the time series of extreme precipitation events in recent 48 years is constructed， by which the characteristics of temporalspatial variations of extreme precipitation events are analyzed. The results show that the interannual variation of extreme precipitation is remarkable over the Huaihe River Basin in rainy season， and the amount of extreme precipitation corresponds well with the droughts and floods. The frequency of extreme precipitation events greatly affects the amount of total precipitation in rainy season. The consistency distribution is the main spatial mode in the frequency of extreme precipitation events in the Huaihe River Basin， which can be divided into five main regions: central and eastern， central and north， southwest， northwest， and southern. The amount and frequency of extreme precipitation for the Huaihe River Basin have obvious increase trends in general since the 1960s， and the most significant increasing tendency occurred in the central and western Huaihe River Basin in particular. There are periodic variations of 2 to 3 years in the frequency of extreme precipitation events over the Huaihe River basin in rainy season. There occurred an abrupt change around 2003， and the frequency of extreme precipitation events increased significantly at a significant level of 0.05 since 2003.