In the Three Gorges Project (TGP)Gezhouba Project(GP) step power station cooperation hydraulics model test, daily Changing amplitude of TGP power stations releasing discharge is large and that of Gezhouba Project in its reverse regulation is huge with low water head. Aiming at the above mentioned features, different design principles and control methods have been adopted respectively to solve the automatic discharge control problems for two power stations. For the measurement of unsteady flow hydraulics parameters in river between two dams and downstream Gezhouba reach, the supersonic water level sensors and twodimension velocity sensors were used to realize concentrative measurement in real time and automatic data processing. The software adopted modular design. The whole system is simple, clear and efficient. An application example for showing the automatic control and measurement is given.