Abstract: An image reading apparatus which can prevent floating of an original disposed on an original table due to wind pressure when an original cover is opened. As an original holding mechanism having a thrust pin which is slidably guided in a direction perpendicular to an inner face of an original cover between a first position where a front end thereof is protruded from the inner face of the original cover and a second position where the front end thereof is positioned substantially the same level of elevation as the flexible sheet. The front end of the thrust pin is protruded from the inner face of the original cover by a pressing force of a spring or own weight of the thrust pin so that it has been contacting to a rear face of the original by protruding from an inner face of the original cover while the original cover has been opened.