To our knowledge, this is the first report of asteroid hyalosis giving rise to spurious automated refraction readings. A patient with asteroid hyalosis had uneventful phacoemulsification with intraocular lens implantation. Using a Nikon autorefractor, the postoperative refraction was +13.0 diopters (D); retinoscopy revealed that it should be +1.0 D. Asteroid hyalosis changes the optical quality of the vitreous and can cause an incorrect reading from automated equipment such as autorefractors and A-scan ultrasound scanners. In patients with asteroid hyalosis, results from autorefractors should be viewed in conjunction with clinical findings.