Open and impartial dispatching is widely used in China at present. Load forecast and hydropower schedule are the foundation of thermal power generation scheduling, and are generally more precise when the forecast time is more recent. To improve the availability of power generation schedule, rolling prediction and correction are usually used in practical applications. An annual rolling power generation schedule and unit commitment optimization model based on open and impartial dispatching is proposed. The primary goal of proposed model is to meet the need of open and impartial dispatching. At the same time, the model can reduce the start-stop times of thermal generation units and improve the average load rate of thermal generation units so as to improve the economy of power grid operation. The proposed model is a mixed integer linear programming problem, and can be solved by optimization tools, such as CPLEX. The correctness and effectiveness of the proposed model is verified by the simulation results of Guangxi power grid. This work is supported by National Natural Science Foundation of China (No. 51377143).