The development of safe desalination plants with low environmental impact is as important an issue as the supply of drinking water. The desalination plant in Jeddah (Saudi Arabia, Red Sea coast) produces freshwater from seawater by multi-stage flash distillation (MSFD) and reverse osmosis (RO). The process produces brine as by-product, which is dumped into the sea. The aim of this study was to assess the impact of Jeddah desalination plant on the coastal water in the nearby of the plant. Total concentrations of dissolved Cu, Ni, Zn and nutrients in several locations around the plant were analyzed by cathodic stripping voltammetry. The average levels of dissolved Cu, Ni, and Zn on surface in the sampling locations were 15.02, 11.02, and 68.03 nM respectively, whereas the levels at the seafloor near the discharging point were much higher. Distribution of temperature, salinity, nutrients and dissolved oxygen were quite normal both on surface and in depth.