Abstract: Abstract :This article studied the united operation of five hydropower stations and adopted the comparative method. On the same condition, the system was firstly divided into two subsystems, i.e. the Three-gorges cascade and the Qingjiang cascade, modeled and solved respectively by optimal algorithm, and individual operation results were gained. Then, united operation mathematics model of two subsystems was established and solved by decomposing-concordance algorithm, and united operation results we re obtained. At last, calculated results through contrastion indicated that united operation could get more than 1.829 billion kilowatt-hourselectric power.