A voltage regulator has an output MOS transistor connected between a voltage source and an output terminal. A voltage dividing circuit is disposed between the output terminal and GND. An error amplifier receives a reference voltage from a reference voltage circuit and a division voltage from the voltage dividing circuit. A current limiting circuit is disposed between the voltage source and the output terminal. The current limiting circuit has a first MOS transistor connected to the voltage source. A current source circuit is disposed between the first MOS transistor and the output terminal. A resistor is connected to the voltage source. A second MOS transistor is controlled based on a current caused to flow through the first MOS transistor. A third MOS transistor is connected between the voltage source and an output terminal of the error amplifier and is controlled based on a current caused to flow through the resistor. When a current caused to flow through the first MOS transistor reaches a predetermined current, the current limiting circuit controls the output MOS transistor to limit a current outputted through the output terminal.