To provide an image reader and image formation device, capable of correcting uneven luminous power without adding a sensor element or sensor interface.

The image reader, having a document lighting device disposed with light-emitting diodes in an array manner, includes: voltage detection means that detects a forward voltage of the light-emitting diodes, and luminous power control means that controls the luminous power of the light-emitting diodes more than that immediately after lighting by one element or a plurality of elements according to voltage information detected by the voltage detection means.