A method for controlling power of a wind turbine, comprising: predicting (S10) wind resource data in a predetermined future period of time based on historical wind resource data; estimating (S20) a maximum design lifetime that the wind turbine is allowed to consume in the predetermined future period of time based on a remaining design lifetime of the wind turbine, wherein the design lifetime refers to a period of time that the wind turbine operates under a design load; determining (S30) optimal output power of the wind turbine in each wind speed section in the predetermined future period of time based on the predicted wind resource data and the estimated maximum design lifetime; and controlling (S40) the wind turbine to operate in the predetermined future period of time based on the determined optimal output power of the wind turbine in each wind speed section, characterized in that the step of determining (S30) optimal output power of the wind turbine in each wind speed section in the predetermined future period of time based on the predicted wind resource data and the estimated maximum design lifetime comprises: determining a first equivalent load of the wind turbine in the predetermined future period of time based on the maximum design lifetime; and determining, based on the first equivalent load and the predicted wind resource data, optimal output power of the wind turbine in wind speed sections including each wind speed in the wind resource data, to cause an absolute value of a difference between a second equivalent load of the wind turbine in the predetermined future period of time and the first equivalent load to be less than a preset value, wherein the second equivalent load is calculated based on the wind resource data and the determined optimal output power. predicting (S10) wind resource data in a predetermined future period of time based on historical wind resource data; estimating (S20) a maximum design lifetime that the wind turbine is allowed to consume in the predetermined future period of time based on a remaining design lifetime of the wind turbine, wherein the design lifetime refers to a period of time that the wind turbine operates under a design load; determining (S30) optimal output power of the wind turbine in each wind speed section in the predetermined future period of time based on the predicted wind resource data and the estimated maximum design lifetime; and controlling (S40) the wind turbine to operate in the predetermined future period of time based on the determined optimal output power of the wind turbine in each wind speed section, determining a first equivalent load of the wind turbine in the predetermined future period of time based on the maximum design lifetime; and determining, based on the first equivalent load and the predicted wind resource data, optimal output power of the wind turbine in wind speed sections including each wind speed in the wind resource data, to cause an absolute value of a difference between a second equivalent load of the wind turbine in the predetermined future period of time and the first equivalent load to be less than a preset value, wherein the second equivalent load is calculated based on the wind resource data and the determined optimal output power. <EOS>