A solar power supply for an automobile air conditioner includes a switch unit, a solar energy unit, and a control unit. The switch unit outputs a switch signal. The solar energy unit includes a solar panel, a solar charging circuit, a DC (direct current) voltage transformation circuit, and a battery. The control unit receives the switch signal, enables the solar charging circuit and the DC voltage transformation circuit in response to the switch signal to charge the battery and transform the voltage received from the battery to a stable voltage, respectively, and provides the stable voltage to an automobile air conditioner.