The invention relates to the field of comprehensive development and utilization and optimized scheduling of water resources, in particular to a cascade hydropower station multi-object optimal scheduling mixed searching method coupling peak shaving and navigation demands. The function of a navigation counter regulation power station can be fully performed, the peak shaving of a power grid and river channel navigation application requirements are taken into account, and a cascade operation plan which is practical and more reasonable in scheduling is obtained. According to the technical scheme, the minimum of the maximum value of the redundant loads of the power grid and the minimum of the variance of the counter regulation power station downstream river channel water level process are adopted as objects, in the NSGA-II searching process, for the complex constrains of the climbing upper limit, the output fluctuation control limit, the machine starting and shutting down minimum lasting time, the term end water level control and the like, time coupling constraint handling strategies, end water level correction strategies and improved genetic manipulation operators are put forward, so that the searching and solving efficiency of the method can be improved, a calculating result meeting engineering application request is obtained, and the method is suitable for being adopted and popularized in the scheduling operation of a cascade hydropower station with navigation requests.