A switching regulator including an inductor and a switching transistor and having a normal operational mode and a light-load operational mode is disclosed. The switching regulator includes an operational mode switching part configured to switch the normal operational mode and the light-load operational mode, and a light-load detection part configured to detect the light-load state of a load. The light-load detection part is configured to detect the light-load state of the load by a change in the voltage at the connection of the switching transistor and the inductor when the switching transistor is OFF. The operational mode switching part is configured to switch the normal operational mode to the light-load operational mode in response to the detection of the light-load state of the load by the light-load detection part.