A power gating circuit includes a logic circuit, a switching element and a retention flip-flop. The logic circuit is coupled between a first power rail and a virtual power rail. The switching element selectively couples the virtual power rail to a second power rail in response to a mode control signal indicating an active mode or a standby mode. The retention flip-flop selectively performs a flip-flop operation or a data retention operation in response to a voltage of the virtual power rail.