An image reading apparatus includes: a transmitting glass; and a step member that is located upstream of a reading position, at which an image of a conveyed document is read by a reading unit via a transmitting glass, in a conveying direction of the document, and has a document guiding surface at a position away from a surface of a transmitting glass by a prescribed distance and forms a step between the document guiding surface and the transmitting glass. The step member is provided with a protrusion protruding downstream in the conveying direction of the document to form space between the transmitting glass and a downstream part of the step member in the conveying direction of the document.