Non-isolated type LED driving power supply having protection function

The utility model relates to a non-isolated type LED driving power supply having protection function, including a rectifying bridge of which an AC side is connected to the commercial power and a DC side is connected to an LED photoelectric device, a filtering capacitor and a chopper circuit composed of a pulse-width modulator and a power switch tube are connected in parallel between anode and cathode of DC output side of the rectifying bridge, the utility model is characterized in that an LED photoelectric device set and a charging/discharging capacitor are connected in parallel in a like polarity manner to form a capacitance charging/discharging circuit and are then connected with an isolation diode in series based on the same poles, then connected with an inductance coil in parallel to form an inductance discharging loop that is connected to output side of a power switch tube, when the power switch tube is of a short circuit fault, the inductance coil, the power switch tube and the rectifying bridge form a loop to make a fuse tube of the circuit to be broken, so as to protect the circuit.