The invention herein provides an over-current protection system. The over-current protection system includes a sensing device, a comparator, a first transistor, and a second transistor. The sensing device is adapted to sense current flowing to an electrical device. The comparator is adapted to compare a signal received from the sensing device and a reference signal to generate any one of high signal and low signal, the output of the comparator being connected to a control device. The first transistor connected to the output signal of the comparator to control the first transistor, while the first transistor is in a conductive state when the output signal of the comparator is high signal. The second transistor connected to and controlled by the first transistor, while the second transistor is in a conductive state when the first transistor is in the conductive state.