A semiconductor integrated circuit includes an identification information storage, an intermediate clock generator and an operating clock generator. The identification information storage stores identification information of the semiconductor integrated circuit. The intermediate clock generator generates an intermediate clock having a frequency higher than that of a reference clock using the reference clock input to the semiconductor integrated circuit from the outside of the semiconductor integrated circuit. The operating clock generator generates the operating clock having a frequency higher than that of the reference clock and lower than that of the intermediate clock in synchronization with a timing allotted according to the identification information stored in the identification information storage, using the intermediate clock.