Abstract: Global warming has become an important environmental issue, and the water resource is the most direct sector affected by climate change. Global warming will alter the spatial distribution of water resources through accelerating hydrological cycle. In further, shortage in water resources would become more obvious, aquatic environment systems would be more deteriorated, and flood threats would be aggravated as well. Possible impacts of climate change on water security are discussed in this paper from the aspects of flood-prevention, water supply, aquatic environment, and water engineering security.

Key words: climate change, water security, impact