A semiconductor integrated circuit includes: a first circuit having a plurality of scan chains; a second circuit connected with input/output signals of the first circuit; and a third circuit connected with the second circuit through the first circuit. The plurality of scan chains comprises a first scan chain that contains flip-flops whose input/output signals are connected with the second circuit, and a second scan chain that does not contain any flip-flop whose input/output signal is connected with the second circuit. The flip-flops operate as a shift register at a scan path test, and when the third circuit exchanges signals with the second circuit through the flip-flops of the first scan chain, the second scan chain of the first circuit operates as a shift register.