In this paper the overall fourth-order model of the CCM photovoltaic grid-connected interleaved flyback micro-inverter is established. The model can analyze the pole-zero locations under different power accurately and improve the control effect of low power. In addition, it is difficult to directly analyze the load imbalance caused by mismatched parameters of the two flyback circuits. In view of the above problem, a sliding mode controller is designed for the current sharing. The problem of load imbalance caused by different parameters of the two flyback is solved, and the output current is improved. A prototype of 250W PV micro-inverter has been built to verify the effectiveness of the proposed modeling and the control approach.