The authors present a clinical material comprising 94 children (55 boys and 39 girls) with unilateral (28) or bilateral (66) retinoblastoma. The period of observation amounted 5 to 15 years. In 84 children they found advanced changes responding to the fifth grade of the Reese-Ellsworth classification. In 14 cases the tumor expanded behind the eye ball or there was its recurrence. From this group 11 children (78.6%) died. The treatment consisted on application of plates with 60Co, xenon photocoagulation, enucleation, exenteration of the orbit, secondary irradiation of the orbit. The risk factors of the incidence of the orbital changes are discussed.