A DC power conversion circuit having self-auxiliary power and self-protection against a short or open load circuit includes a DC voltage source, a driving circuit, and an auxiliary circuit. The DC voltage source is used for providing a DC power. The driving circuit includes a switch, a first resistor, a control signal generator, a second resistor, a diode and an inductor. The switch is used for conducting or cutting off an electrical connection according to an incoming control signal. The control signal generator senses voltage of the first resistor to generate the control signal. The inductor is coupled between the first resistor and a load circuit. The auxiliary circuit is parallel to the inductor and includes an auxiliary capacitor and an auxiliary diode. The auxiliary capacitor is coupled between the first resistor and the second resistor. The auxiliary diode is coupled between the inductor and the auxiliary capacitor.