An overcurrent protection circuit for a voltage regulator has a first transistor having a gate for connection to a gate of an output transistor of the voltage regulator, a resistor connected to a drain of the first transistor, an output voltage detecting transistor having a gate connected to an output terminal of a dividing resistance circuit of the voltage regulator, and a current mirror circuit having an input terminal connected to the drain of the output voltage detecting transistor. A second transistor has a gate connected to the drain of the first transistor and a drain connected to an output terminal of the current mirror circuit. A third transistor has a gate connected to the output terminal of the current mirror circuit and a drain for connection to the gate of the output transistor of the voltage regulator.