Water can make a substantial contribution to human life for drinking as well as purposes related to human life and human nature. Because of increasing demand for water, there is a need for dam construction in preparation for agricultural purposes, drinking, industry and also flood control, power generation, etc. Simultaneously, they have had a considerable impact on the environment. A large range of potential impacts and hazards linked to the exploitation of dams and reservoirs, such as: (i) Major change in flow regime, thermal regime, physico-chemical cycles, (ii) reduction or loss of biological diversity, particular in aquatic species, (iii) greenhouse gas emissions, (iv) increases in the number of infectious disease and accumulation of heavy metals in food web...Therefore, there are various potential health risks of the environment and residents. However, whilst dam effects are very well documented elsewhere in the world, little or no information about negative effects of dams on the environment is available from Vietnam. Consequently, this paper provides a brief review of the environmental impact of dam constructions and after that, we will investigate some strategies to deal with the effects for Vietnam. By the way, we give some insight into the first studies on the impacts of dams on the environment, which focuses on aquatic species was also noted in paper.