The Mekong River is one of the largest river in South East Asia with 4,500 km long and 160 million ton/year sediment discharge. Sediment supply mainly composes of clay, silt and sand deposited under hydrodynamic characteristics of monsoon regime. Since the last 3000 years, the progradational delta has evolved from a tide-dominated delta to the present mixed tide- and wave- dominated delta among Mekong and Bassac river areas, meanwhile, tide-dominated delta has be€m characterized in the Ca Mau delta margin. These changes are well recognized by the depositional process and geomorphological characteristics. Progradational rate is approximately of 820 m/y in the mixed tide- and wave- dominated delta to be smaller than those of the tide-dominated delta reaching 40-60 m/y in the last 2.000-3.000 years. Influence of global climate change and sea-level rising is recognized in the coastal area of Mekong delta. In the last 50-60 years, coastal erosion has been occurred severely at some places in. Tra Vinh and Ca Mau provinces. Coastal erosion has become more sereous due to human activities such as deforestation, sand mining at the coastal areas and reduction of sediment supply to the delta by dam construction in the upstream. Studying delta evolution and coastal changes in several tens to hundred years plays important role in assessing impacts of climate change and sea-level rising to cuastal zone to predict future changes.
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