The present invention discloses a power supply stabilizing circuit having noise suppressing mechanism configured to drive a voltage-control oscillating circuit that includes a current-adjusting N-type transistor including a drain, a source and a gate and an adjusting voltage generation circuit. The drain receives a first operation voltage. The source generates a power signal to the voltage control oscillator circuit. The gate receives an adjusting voltage. The adjusting voltage generation circuit operates according to a second operation voltage higher than the first operation voltage and receives a reference voltage that is a division of the first operation voltage to generate the adjusting voltage. The adjusting voltage is a sum of the reference voltage and a threshold voltage of the current-adjusting N-type transistor such that the current-adjusting N-type transistor operates in a saturation region to keep a current variation amount of the power signal smaller than a predetermined value.