Objective To explore the characteristics and diagnostic values of ultrasound examination of retinoblastoma (RB).Methods The ultrasound and CT features of 210 eyes (162 patients) with pathologically confirmed RB were analyzed retrospectively. Results The ultrasonography image of those RB eyes were all characterized by substantial masses in the posterior segment of the eyeball, shown as spherical, hemispherical and irregular in shape, and even filled the entire eyeball. Calcification within the mass was observed in 197 eyes of 149 patients (92.0%), but not observed in 13 eyes of 13 patients (8.0%).Colorful blood flow signals extended from the central retinal vessels could be seen inside the masses of all patients. Ultrasound diagnosis was consistent with the pathological diagnosis in 92.0% RB cases. CT examination revealed calcified speckles or plaques in 167 eyes from 145 patients (89.5%), consistent with the pathological diagnosis of RB.Conclusions Ultrasonography can show the tumorprime;s shape, size, internal features and the range of orbital involvement. It is a valuable clinical tool in the diagnosis of RB.