Abstract: The flood disaster of the Mekong Delta has always been a hot concern to the international community.The unclear flood characteristics have become a shortcoming restricting the flood control in the region.Based on long series of hydrological data measured at the representative station Kratie Station in the Mekong Delta, we evaluated the flood characteristics and evolution laws by using sliding t-test, Morlet wavelet analysis and flood year division.The results showed that:(1) the average starting and ending dates of the main flood season in the Mekong Delta is from June 30th to November 2nd.In recent years, the main flood season was prone to occur extreme conditions, especially the occurrence of long flood season.(2) The peak flow time is concentrated in August to September, and flood duration is about 90 days on average.(3) The peak flow of Kratie Station is high and the flood volume is large, and the maximum 90-day flood volume and peak flow sequence have a periodic transformation law of 35～37 a.(4) The combination of peak flow and flood volume in Kratie Station was varied, and the variation laws of peak flow and flood volume are basically consistent except for a few years.The research results can provide scientific basis for understanding the complex hydrological law of the Mekong Delta.