A switching circuit is disclosed. The switching circuit includes a normally-on switching element, a normally-off switching element, a switching unit and a power source. The drain of the normally-off switching element is electrically connected to the source of the normally-on switching element. The source of the normally-off switching element is electrically connected to the gate of the normally-on switching element. The power source and the switching unit are configured to form a serial-connected branch. A first terminal of the serial-connected branch is electrically connected to the drain of the normally-off switching element. A second terminal of the serial-connected branch is electrically connected to the source of the normally-off switching element.