An image reading device includes first carriage, a stepper motor, a shakiness level calculating section, and a timing adjusting section. The first carriage reads an image of a document to be read loaded on a document table. The stepper motor moves the first carriage relative to the document. The shakiness level calculating section calculates a shakiness level of the image, indicating shakiness of the image during reading by the first carriage, based on image data read by the first carriage with respect to a reference image incorporated into the document table. The timing adjusting section adjusts a rise timing of a step signal input to the stepper motor in accordance with the shakiness level that is calculated.