The object of the present invention is to provide an image reading apparatus having a large depth of field and being compact in size.The image reading apparatus includes a light source, an imaging optics system, an image pickup device unit, a memory, and a processor. The imaging optics system has a plurality of cells each being an independent optics system arranged in a main scanning direction, and arranged in two rows in a sub-scanning direction. In each of the cells, a first reflective light-gathering optical element, a first plane mirror, an aperture, and a second reflective light-gathering optical element are arranged in this order from a document, and the aperture is arranged at the back focal point position of the first reflective light-gathering optical element to form a telecentric optics system at the side of the document.