The invention provides a method for suppressing DC components in grid side current of a grid-connected inverter. The method includes the steps of acquiring output current in a main power circuit, converting the collected signal into a digital feedback signal iLf; calculating the digital feedback signal iLf in a virtual capacitor module, subtracting the digital feedback signal iLf from a voltage reference signal vref to obtain a modulation signal vr, a DPWM module modulating the modulation signal vr to form a duty cycle signal d, and duty cycle signal d controlling the on-off of the switch tubein the main power circuit and adjusting the main power circuit. According to the method provided by the invention, the size of the prototype can be effectively reduced, the power density is improved,the loss is reduced, and the reliability of the system is improved.