Abstract: Aiming at the problems of insufficient control accuracy, poor robustness and anti-interference of traditional PI control for photovoltaic grid connected inverter, a sliding mode control with double closed loops is proposed(SMC). In this strategy, the voltage outer loop and current inner loop are used to stabilize the output voltage and output current respectively, and the integral sliding mode control is used in both inner and outer loops to enhance the robustness of the system. In addition, aiming at the problems of low efficiency and inaccuracy caused by manual adjustment of controller parameters, a multi-objective particle swarm optimization algorithm is proposed particle swarm optimization(PSO) is used to adjust the parameters of the sliding mode controller, which makes the controller have the advantages of high tracking accuracy, fast response speed and small overshoot. Finally, the superiority and feasibility of the proposed strategy are proved by MATLAB/Simulink simulation experiments.