In image reading apparatus capable of performing a read-while-feed operation in which an original is read while being fed by an image sensor placed at a fixed position, presence/absence of dust and/or dirt on a platen is detected, and, in a case where dust and/or dirt are detected at all of a plurality of predetermined positions by said detector, the read-while-feed operation is inhibited and the presence of dust and/or dirt is notified to a user. When, removal of dust and/or dirt on the platen is detected in a state that the read-while-feed operation is inhibited, the read-while-feed operation is allowed.