Micro-inverters are widely used in power conversion from photovoltaic panels and fuel cells. The flyback-based differential inverter is a good candidate for micro-inverters as it provides the necessary isolation required for safety. In this paper, an active power decoupling control method is adopted in order to minimize the pulsating power between the renewable energy source and the grid. The working principle of the micro-inverter under active power decoupling is analyzed. Simulation results show that for the micro-inverter working in discontinuous conduction mode (DCM), the low-frequency current ripple is reduced dramatically using an active power decoupling control method.