Abstract: Accurate ocular biometrics are critical to intraocular lens (IOL) implantation or refractive surgery. Lenstar LS900 as a new optical low coherence reflectometry device is well received in both clinical and research work,due to its noncontact measurement, single alignment requirement, more parameters and high resolution, etc. This article will review the principle, characteristics of Lenstar, the research and clinical applications on measuring axial length, anterior chamber depth, corneal curvature, central corneal thickness, lens thickness, vitreous chamber depth, retinal thickness, choroidal thickness, horizontal iris width, pupil size, visual axis decentration and IOL estimator, etc.  (Int Rev Ophthalmol, 2012, 36: 93-97)