In recent years，with the continuous progress of science and technology and the rapid development of social economy in China，the energy problem has been widely concerned by people from all walks of life.Now many industries in China are implementing energy saving measures.With the accelerating process of urbanization in China，the energy consumption of water supply industry is also increasing.The second water plant in Shanggao County，Yichun City，Jiangxi Province is studied in this aritcle.According to statistics，the power cost of water supply system is the most important part of all water plant expenses，accounting for more than 60% of the total water production cost.Therefore，for the operation cost of water plant，energy saving and consumption reduction can play a crucial role.Through the research and transformation of the water plant，the following conclusions are drawn.Based on the actual measurement and analysis of the pumping station in the existing water plant，this paper puts forward the transformation of the pumping station by frequency conversion debugging，and makes an economic comparative analysis of the energy consumption of the transformed pumping station.The analysis shows that the effect of energy saving and consumption reduction is remarkable.Through the study of disinfectant consumption，a better drug supply method and route are obtained.Under the premise of ensuring the safety of water quality and quantity，the cost of water supply is reduced and the energy consumption is saved.