An image reading apparatus includes: a lamp shining light on a target original document to be read; a lamp operating circuit for turning on the lamp; an image sensor receiving light shone from the lamp to the original document and reflected from the original document, for generating image data; a control section outputting a lamp control signal for controlling turning-on and -off of the lamp to the lamp operating circuit; and a lamp control circuit, separate from the control section, outputting a lamp control signal for controlling turning-on and -off of the lamp and, when a main power switch of the apparatus is turned on, permitting the lamp to be turned on before the control section is activated.