Taking 2×330MW direct air cooled unit as an example, the general layout and the overview of the building design of the power plant water, the water source and the water treatment center were introduced. The feasibility to adopt the field bus technology in the water treatment center was analyzed. By adopting the field bus control technology in the water treatment center, the transmitted information is changed from analog signals into digital signals, the devices have functions of intelligent diagnosis and predictive maintenance, and the digital control of the water treatment center is realized. Using the technical advantages of the field bus control technology fully, such as the fewer occupied area caused by centralized control, the lower investment and the higher safety and reliability, the operation and management level of the water treatment center are improved greatly.