Objective To study the development of the rostral migratory stream (RMS) of mice and the proliferation and apoptosis of neural stem cells in RMS at various postnatal ages.Methods With 5-bromodeoxyuridine (BrdU) assay and Caspase-8 immunofluorescent staining, the neuroproliferation and cell apoptosis in RMS were investigated.Results In early postnatal phase, there were many proliferative cells in the brain, especially in subventricular zone (SVZ) and RMS. With age increasing, the stem cells in the brain decreased. In the adult, the stem cells in the neocortex were hardly found except in SVZ and RMS areas. When the proliferation of stem cells was companied with apoptosis during RMS development, there was a positive correlation between cell proliferation and apoptosis.Conclusion There is an important signification for the neuroproliferation and cell apoptosis in RMS. Through cell apoptosis, the migration and differentiation of neural stem cells in RMS are regulated.