To provide a semiconductor integrated circuit being capable of widely using an input-voltage range even when a power-supply voltage is low, and having an operational amplifier having a stable gain.

The semiconductor integrated circuit has an input circuit 100 differentially amplifying input signals supplied to input terminals 1 and 2, respectively, an active load 101 for single-end outputting a signal amplified by the input circuit 100, and a bias circuit 102 as a circuit for making a bias current for the active load section 101 flow. The semiconductor integrated circuit further has a first amplifier 200 amplifying a single-end output from the active load 101 and outputting the output to the outside through an output terminal 3, and a second amplifier 300 being connected to the first amplifier 200 and making a current from the outside flow through the output terminal 3.