The ocular ultrasonography has advanced significantly in recent years.A-mode ultrasound is extensively used for ocular biometry.With B-mode ultrasound we can acquire two-dimensional images.Anterior segment images can be obtained by ultrasound biomicroscopy.Color Doppler flow imaging displays blood flow information of normal and pathological tissues.Contrast-enhanced ultrasound can even be used for quantitatively analyzing the perfusion characteristics.Ocular ultrasound has been widely utilized for diagnosis and follow-up of eye diseases although with some limitations.Affected by penetration and resolution,ocular ultrasound is limited in diagnosis of special cases,and sometimes leading to false positive or false negative results.This review mainly introduces the indications and limitations of ultrasonic diagnosis,and also the characteristics and advantages of each method.