A reading device includes an emission unit that emits light; a first reflecting unit having a first reflecting surface that reflects the light emitted by the emission unit toward a document; a second reflecting unit having a second reflecting surface that reflects the light reflected by the first reflecting unit and specularly reflected by the document; a first support unit that supports the first reflecting unit and the second reflecting unit and fixes a relative position and a relative orientation between the first reflecting surface and the second reflecting surface; and a second support unit that supports the first support unit such that at least one of a position and an orientation of the first support unit is adjustable.