To provide an original reader capable of effectively preventing useless power consumption.

When it is determined that an original is placed at a set position even when a prescribed time elapses after the reading of the original placed at the set position (Yes in a step S204), the power state of an original reader is changed over into an energy saving mode. Thus, even when a user forgets to take the original after the reading of the original, the power state of the original reader is changed over into the energy saving mode, based on a clocking result. Consequently, useless power consumption is prevented during a period till the user recognizes that the original has been left.