The invention provides a voltage stabilizing device. In the voltage stabilizing device, a signal detecting and amplifying circuit detects an operating voltage of the functional circuit, amplifies the detected operating voltage and outputs the amplified voltage signal to a logic processing circuit; the logic processing circuit adjusts a first control signal according to the amplified voltage signal and outputs the adjusted first control signal to a feedback voltage signal generating circuit; the feedback voltage signal generating circuit adjusts a feedback voltage signal according to the adjusted first control signal and outputs the adjusted feedback voltage signal to the logic processing circuit. Moreover, the logic processing circuit further adjusts a second control signal according to the adjusted feedback voltage signal and outputs the adjusted second control signal to the functional circuit, and thereby controls an output voltage of the functional circuit to be kept stable.