The subject of accuracy in intraocular lens(IOL) power calculation in eyes after corneal refractive surgery is a real problem. It is well known that using routine keratometry and standard equations to determine the IOL power for cataract surgery in patients who have had excimer laser corneal surgery often leads to unwanted postoperative hyperopia.This paper reviews the sources of prediction error and analyzes methods to attempt to improve the accuracy of IOL power calculation.