As the development of surgery related technology and clinical application of premium intraocular lens (IOL), cataract surgery has been in the era of refractive surgery. To restore the refractive system by surgery has been focused on and challenges have been brought up in preoperative measurement and accurate IOL power calculation methods. It is necessary to know developments of the related measurement technologies and the possible error resources to decrease refractive errors. Different means of measuring axial length, cornea curvature and anterior chamber depth were related here, co-operated with varied IOL power calculation methods, such as standard power, traditional formulas and real ray tracing method. Researchers should pay close attention to the preoperative measurement and IOL power calculation methods in cataract patients, the combination of accurate measurement with different calculation methods can help to acquire an increasingly satisfactory visual result.