An image reading device includes an imaging device including a plurality of imaging elements, a color measuring unit that detects color of an object at a color measurement area, a calibration plate having a surface on which a plurality of color patches is formed, and a processor that causes the color measuring unit to read the plurality of color patches while changing a relative position between the plurality of color patches and the plurality of imaging elements to output color measurement results of the plurality of color patches, and generates a set of reference values for the plurality of color patches based on the color measurement results of the plurality of colors. The set of reference values are compared with the reading results of the plurality of color patches to generate a set of correction values for correcting the reading results of the plurality of color patches.