The present invention discloses a frequency-changing voltage regulation circuit, which applies to a power supply device that has a booster unit and a power conversion unit. The booster unit modulates an input power and converts the input power into a boosted power. The boost control circuit is coupled to the frequency-changing voltage regulation circuit of the present invention. The frequency-changing voltage regulation circuit comprises: a voltage detection circuit and a frequency setting circuit. The voltage detection circuit detects the input power sent to the booster unit and generates an input level signal according to the value of the input power. The frequency setting circuit generates a reference frequency signal corresponding to the input level signal and uses the reference frequency signal to modulate the frequency that the booster unit performs power conversion.