Abstract: 　Objective　To investigate the proliferation of endogenous neural stem cells in rat brain in the course of experimental Streptococcus pneumoniae (Sp) meningitis. Methods Three-week-old SD rats were divided into Sp meningitis group (n=28), control group (n=16) and sham operation group (n=16). The rats in Sp meningitis group were inoculated with Sp by cisternal puncture and rats in control group were injected with normal saline. Four rats each were individually sacrificed at 24 h, 5, 14 and 21 days after inoculation and the expressions of Bromodeoxyuridine (Brdu) in the subventricular zone and hippocampus of the rats were dynamically detected by immunohistochemical method. Results Brdu positive cells were observed in the bilateral subventricular zone of the rats in Sp meningitis group, control group and sham operation group at 24h, 5, 14 and 21 days after inoculation. The number of Brdu positive cells in Sp meningitis group was increased initially at 24h after inoculation, reaching a peak at 5^th day and then decreased. There was difference among different time points (P<0.05). At 24h, 5 and 14 days after inoculation, the number of Brdu positive cells was respectively significantly higher in Sp meningitis group than that in control group and sham-operation group (P<0.05). At 21^th day after inoculation, the number of Brdu positive cells in Sp meningitis group was similar with control group (P>0.05), while different from sham operation group (P<0.05). Conclusions Sp meningitis can stimulate the proliferation of endogenous neural stem cells in the subventricular zone of rat brain.