The objective was to assess epidemiologic aspects of retinoblastoma development in Karachi, Pakistan. Incident cases, diagnosed clinically or microscopically and registered at Karachi Cancer Registry (KCR) during 1st January 1998 to 31st December 2002 were reabstracted, rechecked and reanalyzed for this purpose. One hundred and one cases of retinoblastoma were reported to KCR over the 5 years (1998-2002). Fifty-seven were residents of Karachi, 34 (59.6%) males and 23 (40.4%) females. The gender ratio (M:F) was 1.5. The mean age at diagnosis was 3.96 years (95% CI 2.92; 4.99) and 3.85 years (95% CI 2.72; 4.98) in males and females respectively. The annual crude incidence of retinoblastomas in Karachi was 4.0/100,000 and 2.4/100,000 in children under the age of 5 and 10 years respectively, the corresponding age standardized rates being 5.3/100,000 and 4.8/100,000. The age groups at risk of developing retinoblastoma, associated morbidity and possibility of almost 100% 5-year survival with available treatments, calls for ophthalmologic screening of all infants below 1 year, and high-risk children until the age of 7 years. In order to detect retinoblastoma, as early as possible, health education for parents and health providers, and improved training of ophthalmologists is essential. Genetic testing for siblings and children of retinoblastoma cases and identification of high-risk children would be helpful, but lacks financial feasibility in developing countries at present. Future health care planning should focus on capacity building for neonatal ophthalmologic screening, handling of parents’ and children’ emotional reactions and opportunities for education, occupational training and cosmetic rehabilitation for surviving retinoblastoma patients.