The invention discloses a water diversion project operation mode converting method. The water diversion project operation mode converting method comprises the four basic steps that a hydraulics simulation model under regulation of a brake pump group is established; it is judged that what kind of water diversion project operation mode is selected; whether the converting conditions are achieved or not is judged; and the operation mode is converted. The water diversion project operation mode converting method is a dispatching control method applied to convert the operation mode of a water diversion project under the emergency working condition and used for solving the problems that during emergency regulation of the water diversion project, water flow response and recovery characteristics arepoor, and storage volume regulation and emergency demands are inconsistent.