An image processing apparatus includes a processing target selection unit. The processing target selection unit inquires which image data obtained by a conveyed-document reading unit or by a fixed-document reading unit, to be set as a processing target when a user determination unit has determined that users are identical, determines image data obtained by a conveyed-document reading unit as a processing target when the user determination unit has determined that the users are not identical and a determination unit has determined that the document on the platen is a left document, and inquires which image data image data obtained by the conveyed-document reading unit or by the fixed-document reading unit, to be set as the processing target when the user determination unit has determined that the users are not identical, and the determination unit has determined that the document on the platen is not a left document.