Abstract: A voltage regulator circuit with a low quiescent current for generating a stable output voltage includes a standby mode controller for generating an enable signal according to a standby signal, a reference voltage generator for receiving an operation voltage and generating a reference voltage, an amplifier for receiving the reference voltage and the output voltage and generating an amplified voltage, and a switch unit for receiving the operation voltage and generating the output voltage at an output terminal. The enable signal is kept enabled when the standby signal is disabled, and the enable signal is periodically enabled when the standby signal is enabled. The amplifier works only when the enable signal is enabled. The switch unit is controlled by the enable signal, and is turned on only when the enable signal is enabled. So, the quiescent current of the voltage regulator circuit in the standby mode can be greatly reduced.