The quality of water resources in coastal and island regions is at risk from rising sea level and changes in precipitation. Rising sea level and the occurrence of drought can increase the salinity of both surface water and groundwater through saltwater intrusion. The present chapter provides a review of the observed and expected impacts of climate change on water quality in various water bodies of coastal regions and offers possible strategies for reducing these impacts. These strategies are very important to maintain the suitability of different types of water bodies for various purposes (such as irrigation, industry, etc.)