Provided is an alternating current (AC) and direct current (DC) power supply device in which normal power and power of a solar cell is used to supply not only AC power but also DC power, particularly, power of a solar cell is first supplied as DC power or is charged in a battery, and after battery charging, residual power is converted to AC power via an inverter so as to replace normal AC power or to transmit AC power to the outside. Accordingly, an SMPS power supply method in which AC and DC power are supplied at the same time may be provided, and moreover, power of a solar cell may be effectively used.