An image reading apparatus includes a transport unit which transports a document, and reading units which read an image of the document which is transported. It is assumed that an operation of reading an image when specific setting information is not input to a control device of the image reading apparatus is set to a first reading mode, and an operation of reading an image when specific setting information is input to the control device is set to a second reading mode. In this case, in the second reading mode, image data of an image with a resolution which is equal to that in the first reading mode is generated, while causing the reading units to read an image from a document which is transported by the transport device at a lower speed than that in the first reading mode.