The invention relates to a switch power circuit capable of selecting five shifts and outputting 3A. The switch power circuit comprises a voltage transformation module, a rectification module, a capacitor filtering module, a voltage stabilization module, a control module, a shaft regulation module and an LC filtering module. Filtering capacitors with different capacitance values are selected to filter a current after being rectified by the rectification module, not only a certain voltage ripple is filtered by connecting different capacitors in parallel, and a large burr ripple is removed by connecting some small capacitors in parallel; and moreover, output currents of different voltages can be selected by a buck switch type integrated voltage stabilization chip and the shift regulation module, and the demands of different electrical appliances on different voltages during charging are satisfied.