1. An image forming apparatus, comprising: a recording sheet type detection device configured to automatically detect a type of a recording sheet; a setting device configured to set an image forming condition by an operator, the image forming condition including the type of the recording sheet; an image forming device configured to form a visible image on the recording sheet; a sheet feeding device configured to feed the recording sheet to the image forming device; and a controller configured to control the image forming apparatus not to form an image on the recording sheet when the image forming condition with regard to the type of the recording sheet set by the operator does not match the type of the recording sheet detected by the recording sheet type detection device.