The power supply module includes a switching power circuit, a switching unit, a power storage unit and a control unit. The switching power circuit is coupled between an input terminal and an output terminal, and used to convert a first voltage to a second voltage. The switching unit is connected to the switching power circuit in parallel. The power storage unit is coupled to the output terminal. The control unit is coupled to the switching unit and controls the switching unit to turn on selectively according to a detecting signal corresponding to a charging or discharging status of the power storage unit to output the first voltage to the output terminal.