An image forming apparatus includes: an image forming unit; a power supply controller controls the image forming apparatus to operate in a power saving mode, in which supply of power to the image forming unit is cut off, and a normal mode; and a plurality of interfaces that receives a transition command for transitioning from the power saving mode to the normal mode. The power supply controller is configured to perform: an interface-power supply process of supplying power to at least one interface; a determining process of determining whether availability is high or low for an operating interface receiving power supply in the interface-power supply process; and a changing process of changing a power supply target from the operating interface to an idle interface when the availability of the operating interface is determined to be low.