A switching capacitor power conversion circuit includes: a conversion capacitor, plural conversion transistors and an output capacitor connected to an output node. In a switching conversion mode, the switching capacitor power conversion circuit switches connections of the capacitor to convert the input power into an output power on an output node. During a first pre-charging period, a first conversion transistor is controlled to provide a first pre-charging current to pre-charge the conversion capacitor to a predetermined voltage level, and the output capacitor is prevented from being charged. During a second pre-charging period, a second conversion transistor is controlled to provide a second pre-charging current to pre-charge the output capacitor to the predetermined voltage level, and the second pre-charging current supplies a load current to a load circuit.