A method of operating a micro inverter of a solar power system includes following steps: First, an output power value of a solar photovoltaic module is acquired. Afterward, it is to judge whether the micro inverter executes a power boosting mode. If the power boosting mode is executed, a maximum output power of the micro inverter is boosted from a rated output power value to a maximum output power value. Finally, it is to judge whether the output power value of the solar photovoltaic module is greater than the maximum output power value. If YES, the maximum output power value is outputted from the micro inverter.