Abstract: Cadmium, which exists in cadmium sulfide ore in nature, is a toxic metal element, which has the characteristics of difficult degradation, low toxicity, high stability and accumulation, and some cadmium is distributed in water, soil, animals and plants,this heavy metal will cause great harm to human health. When cadmium enters the human body, it often takes a long time to be excreted from the body. Usually, the biological half-life of cadmium in human renal cortex is 10～30 years. In recent years, cadmium pollution accidents often occur in various parts of China, which have a very serious impact on the normal production and life of local residents. The government and all sectors of society are also very concerned about the production safety of cadmium and its impact on the environment. This paper mainly described the treatment technology of cadmium pollution in water environment.