An image reading apparatus includes a carriage, a carriage detector, and a control unit. The carriage detector outputs a detection signal of the carriage when the carriage is at the home position, and outputs a non-detection signal of the carriage when the carriage is located closer to a document size reading position than a predetermined position between the home position and the document size reading position. The control unit moves the carriage to the home position when the image reading apparatus enters a sleep mode, keeps the carriage detained while performing initialization after the sleep mode is cancelled, and moves the carriage, upon receipt of a scanning instruction after the initialization is completed, toward the document size reading position in the case where the carriage detector outputs the detection signal of the carriage.