In this study,cells from the cerebral cortex of fetal rats at pregnant 16 days were harvested and cultured with 20 μg/L neurotrophin-3.After 7 days of culture,immunocytochemical staining showed that,22.4％ of cells were positive for nestin,10.5％ were positive for β-Ⅲ tubulin (neuronal marker),and 60.6％ were positive for glial fibrillary acidic protein,but no cells were positive for O4 (oligodendrocytic marker).At 14 days,there were 5.6％ nestin-,9.6％ β-Ⅲ tubulin-,81.1％ glial fibrillary acidic protein-,and 2.2％ O4-positive cells.In cells not treated with neurotrophin-3,some were nestin-positive,while the majority showed positive staining for glial fibrillary acidic protein.Our experimental findings indicate that neurotrophin-3 is a crucial factor for inducing neural stem cells differentiation into neurons and oligodendrocytes.