MTT assay was presented in this paper and used in 3 cases of retinoblastoma afert enucleation to evaluate the clinical effect of different chemotherapeutic agents.The results showed that the sensitivity of anticancer agents were various in different cases of retinoblastoma.The combining treatment of tow anticacer agents together was seemingly preferable to a single use.When a single drug was chosen,it was advisable to use carboplatin,cisplatin,mitomycin C or etopside.If a combination of 2 anticancer drugs were applied,vincristin with carboplatin or cisplatin will give a better effect than others,but vincristin is not sensitive when applied alone. （Chin J Ocul Fundus Dis,1993,9:207-209）