AIM: To explore the impact of insulin-like growth factor-1 receptor α (IGF-1Rα) on the differentiation fate of optic-cup-derived retinal stem cells (OC-RSCs) into retinal ganglion cells (RGCs) in vitro. METHODS: OC-RSCs were isolated from optic cups of rats on embryonic day 12.5, and high-purity OC-RSCs were obtained by conditioned culture and passage. Differentiation of OC-RSCs into RGCs under different serum concentrations was examined using flow cytometry, and the serum concentration with high interference with differentiation ratio was selected. Furthermore, the effect of blocking IGF-1Rα on the differentiation of OC-RSCs into RGCs was analyzed through immunocytochemistry and Western blotting. RESULTS: Immunohistochemical analysis revealed IGF-1Rα was highly expressed in rat embryos at day 12.5. OC-RSCs were isolated and purified, and high-purity OC-RSCs were obtained. When 2.5% serum was administered, the ratio of differentiated RGCs (Thy-1.1 positive) decreased significantly, and the results of immunoblotting also confirmed the blockade of IGF-1Rα reduced Thy-1.1 protein expression. CONCLUSION: IGF-1Rα blocking can reduce the differentiation of OC-RSCs into RGCs.