Abstract: A hybrid MPPT scheme based on fitting optimization backstepping sliding mode control is proposed in this paper. Firstly,the scheme is based on the P-V characteristic curve of photovoltaic power generation system. The cubic interpolation function is used to fit the reference voltage at the maximum power point Vref. Then,based on the Vrefand backstepping sliding mode control principle,a controller is designed and the duty cycle is controlled by PWM modulation,so that the controller can track the maximum power point quickly and effectively under different environmental conditions. Finally,the effectiveness of the proposed scheme is verified by Matlab/Simulink simulation,and compared with other classical methods. The results show that the method has high tracking speed,low steadystate power fluctuation and better tracking performance.