Abstract: A capacitance charge device with adjustable clamping voltage is disclosed in the invention, which includes a high-farad capacitance and a power supply device for charging to the high-farad capacitance. In addition, a switch device is connected between the power supply device and the capacitance, and through the on/off operations of the switch device, the on/off conductions between the power supply device and the capacitance can be controlled. Besides, a clamping circuit is connected between the switch device and the capacitance and also connected to the output terminal of the power supply device. In addition, the clamping circuit has a clamping voltage, which can be compared with the actual voltage so as to control the on/off operations of the switch device and in turn control the on/off conductions between the power supply device and the capacitance. In addition, the invention can constrain the battery voltage in the clamping voltage of the clamping circuit.