Surface water resources in the Mekong Delta are strongly influenced by external driving factors including upstream discharge, local rainfall, and tidal regimes. In addition, internal factors (development of flood control dyke systems, diverting flow constructions, and coastal protection sea dyke systems) also provide forces exaggerating water resources changes locally. Even though the surface water resources in the delta provides vital conditions for development, they are highly subjected to changes induced by local and regional socio-economic development and global climate change. This presentation discusses the trends of changes of the surface water resources in the delta with considerations on analysing impacts of the driving-forces. In addition, discussion on the accumulative impacts of future changes on the surface water resources and consequent possible threats on the sustainable development of the delta are also presented.