An image reader includes: a bottom wall that faces a discharge table of a main body of an image forming apparatus, to which a printed sheet is discharged, with a space formed therebetween, the bottom wall forming a bottom surface of a housing that receives an optical system and including a concave portion recessed into the inside of the housing without including a convex portion protruding toward the outside of the housing in a contactable area having a possibility that the printed sheet comes into contact therewith when the printed sheet is discharged to the discharge table, the bottom wall including the convex portion protruding toward the outside of the housing in the other areas except for the contactable area.