Objective To research the effects of panax notoginseng saponins on proliferation and differentiation of rat hippocampal neural stem cells (NSCs) EM>in vitro/EM> . Methods NSCs of SD rat hippocampus were isolated and cultured in serum.free medium containing bFGF and EGF. The neurospheres were identified by antibodies of nestin, 5.bromodeoxyuridine (BrdU), class β.Ⅲ Tubulin(Tuj-1)and glial fibrillary acid protein (GFAP). The cells were divided into control group, PBS group and PNS treated group, which includes 0.1,0.2,0.4,0.8,1.0 g/L treated group. The clone information rate, proliferation curve and differentiation proportion of NSCs were observed. The cells were divided into control group and 0.4 g/L PNS treated group. Flow cytometry was used to study the effect of PNS on differentiation of hippocampal neural stem cells. Results The NSCs formed neurospheres and grew in floating. They were nestin-positive and BrdU-positive. GFAP-positive and Tuj-1-positive cells appeared after fetal bovine serum(FBS) were added into the medium. Compared with control, the low doses of panax notoginseng saponins (0.1,0.2,0.4 g/L) exhibited no effects on the NSCs proliferation, while high doses of panax notoginseng saponins (0.8 and 1.0 g/L) treatment markedly inhibited the proliferation of rat hippocampal NSCs and the difference had statistical significance ( P<0.05). Treatment of NSCs with 0.4 g/L PNS markedly increased the neurogenesis of NSCs in differential medium, and the difference had statistical significance( EM>P/EM><0.05). Conclusion Panax notoginseng saponins regulates the proliferation and differentiation of NSCs EM>in vitro/EM> , whereas only 200 mg/L panax notoginseng saponins can increase the neurogenesis of rat hippocampal NSCs.