An image reading apparatus including reading means configured to read a document, the image reading apparatus configured to read an image of a document according to a read request transmitted from an external device, the image reading apparatus comprising: reception means configured to receive a state acquisition request to obtain at least information regarding a presence or absence of the document to be read by the reading means from the external device; power supply means, and transmission means configured to transmit information regarding the presence or absence of the document to be read by the reading means to the external device as a response to the state acquisition request, characterized in that: the image reading apparatus further comprises: detection means configured to detect the presence or absence of the document to be read by the reading means, wherein the power supply means is configured, in the case that the reception means receives the state acquisition request when the image reading apparatus is in a power saving state where power supply to the reading means and the detection means is stopped, to supply power to the detection means based on the reception of the state acquisition request; and the transmission means is configured to transmit (S605, S606), as the information regarding the presence or absence of the document to be read by the reading means, the presence or absence of the document detected by the detection means to which the power is supplied by the power supply means. reception means configured to receive a state acquisition request to obtain at least information regarding a presence or absence of the document to be read by the reading means from the external device; power supply means, and transmission means configured to transmit information regarding the presence or absence of the document to be read by the reading means to the external device as a response to the state acquisition request, characterized in that: the image reading apparatus further comprises: detection means configured to detect the presence or absence of the document to be read by the reading means, wherein the power supply means is configured, in the case that the reception means receives the state acquisition request when the image reading apparatus is in a power saving state where power supply to the reading means and the detection means is stopped, to supply power to the detection means based on the reception of the state acquisition request; and the transmission means is configured to transmit (S605, S606), as the information regarding the presence or absence of the document to be read by the reading means, the presence or absence of the document detected by the detection means to which the power is supplied by the power supply means. detection means configured to detect the presence or absence of the document to be read by the reading means, wherein the power supply means is configured, in the case that the reception means receives the state acquisition request when the image reading apparatus is in a power saving state where power supply to the reading means and the detection means is stopped, to supply power to the detection means based on the reception of the state acquisition request; and the transmission means is configured to transmit (S605, S606), as the information regarding the presence or absence of the document to be read by the reading means, the presence or absence of the document detected by the detection means to which the power is supplied by the power supply means.