A semiconductor integrated circuit includes constant current circuit, starter circuit and power supply start-up circuit. In the constant current circuit, first current mirror circuit includes first and second transistors, and second current mirror circuit includes third and fourth transistors that are connected to first and second nodes. In the starter circuit, a potential of first node controls sixth transistor, seventh transistor is connected to third node, gate electrode of the seventh transistor is at ground potential, a capacitance element is connected to fourth node, and a potential of fourth node controls fifth transistor, which supplies start-up current to the constant current circuit via second node. In the power supply start-up circuit, source electrode of eighth transistor is fixed at power supply voltage, gate electrode is at ground potential, and drain electrode supplies power to the other circuits.