Image reading apparatus and image forming system

An image reading apparatus configured to read an image on a sheet conveyed from an image forming apparatus that forms the image on the sheet, the image reading apparatus comprising:

• a conveyance unit configured to convey the sheet in a sheet conveyance direction;
• and
• a reading unit configured to read image information of the sheet,
• wherein 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 configured to support the sensor unit;
• and
• a casing configured to accommodate the sensor unit, the fan, and the supporting member,
• wherein the fan is disposed in a manner of facing the opening of the supporting member on a side, with respect to the opening, different from a side on which the sensor unit faces the opening, and
• wherein the sensor unit and the supporting member are disposed such that a flow path of air that has passed through the opening of the supporting member is formed between the sensor unit and the supporting member.