A semiconductor integrated circuit includes a substrate, a digital circuit formed on a triple well formed in the substrate, a first node configured to supply a well potential of the digital circuit, a second node separate from the first node, and a substrate-potential supplying circuit, formed on the substrate, having an input node to receive an input potential from the second node and an output node to supply a substrate potential to the substrate, the substrate-potential supplying circuit having no direct-current path into which a direct current substantially flows through the input node, and configured to generate at the output node an output potential following the input potential.