The present invention relates to a shapley value method of cascade hydropower station group joint operation benefit allocation, belonging to the field of power industry power station benefit allocation. At present, the benefit allocation problem among a large basin stopcock hydropower station, different development bodies, main stream and tributary segment cascade hydropower station groups is difficult to solve. The method comprises the steps of (1) dividing the sub systems of different benefit bodies in a whole cascade system, (2) establishing the power generation amount largest model of researching a power station group benefit compensation problem, wherein the calculation model of the benefit in the cascade system is largest power generation, (3) obtaining the processing methods of the shapley value method in different calculation working conditions for power station with adjustment ability in a benefit allocation process, (4) according to the definition of the shapley value method, completing the benefit allocation of each sub system, and finally obtaining the benefit allocation of each under different modes. According to the invention, the benefit sharing problem in the hydropower station joint operation is solved, and the method is scientific, reliable and reasonable.