Silver staining technique and computer-assisted image analysis system were used in this study to detect,compare and analyse the nuclear organizer regions(NORs)in human normal retina and retinoblastoma(including differentiated and non-differentiated).The results showed that the mean number of AgNOR per nucleus,the average silver staining area per nucleus and retino of silver staining area to nuclear area in non-differentiated retinoblastoma were much higher than that in differentiated retinoblastoma and normal retina.This might suggest that AgNORs technique and computer-assisted image analysis system have important role in the typing,grading and expectation of progression of retinoblastoma. (Chin J Ocul Fundus Dis,1993,9:202-204)