A document reading apparatus includes an image reading unit, a document conveyance unit, and a hinge mechanism. The document conveyance unit includes a first abutment portion and a second abutment portion. The document conveyance unit includes a first abutment portion and a second abutment portion. The hinge mechanism includes a first member, a first shaft, a second member, a second shaft, a third member, a third shaft, a fourth member, a first urging portion, a second urging portion. The fourth member has a first pair of side plates supported by the third shaft. The second spring is disposed outside the first pair of side plates in an axial direction of the third shaft.

An image reading apparatus includes a conveyance unit and a reading unit. The reading unit includes a transparent member, a sensor unit including a substrate to which an image reading element is connected, and configured to read an image of the sheet through the transparent member, a fan configured to blow air, a supporting member including an opening formed at a position where the opening faces the sensor unit, and supporting the sensor unit, and a casing accommodating the sensor unit, the fan, and the supporting member. The fan is disposed in a manner of facing the opening on a side, with respect to the opening, different from a side on which the sensor unit faces the opening. The sensor unit and the supporting member are disposed such that a flow path of air that has passed through the opening is formed between the sensor unit and the supporting member.