The grid-connected current output from a flyback photovoltaic microinverter is prone to distortion due to nonlinear factors such as switching tube dead zones, driving asymmetry and grid voltage disturbances. Aiming at the traditional PI control which cannot effectively improve the influence of nonlinear factors, this paper proposes an interleaved flyback photovoltaic microinverter based on PI and repetitive control, and in-depth research on the circuit topology, control strategy and the design method of the PI and repetitive controller of this inverter is carried out. Simulation results show that the photovoltaic microinverter grid-connected current with PI and repetitive control is of high quality, with better dynamic performance and anti-interference capability, while realizing the maximum power point tracking.