Objective To investigate the proliferation of endogenous neural stem cells in the rat brain during experimental Streptococcus pneumoniae meningitis.  Methods Three weeks old rats were used to construct the infection group of Streptococcus pneumoniae meningitis, the control group via saline injection, and the shamoperation group. The expressions of bromodeoxyuridine （Brdu） in the hippocampus of the rats were dynamically detected by immunohistochemical method in 24 h, 5, 14, and 21d after injection, respectively.  Results Brdu positive cells were observed in the hippocampus of the infection group of Streptococcus pneumoniae meningitis, the control group, and the sham-operation group at d1, d5, d14, and d21 of inoculation. In the infection group of Streptococcus pneumoniae meningitis, the number of Brdu-labeled cells at 24 h after infection was not changed compared to d5 and d14 level （P>0.05）, but was greater than d21 level （P<0.05）. Compared with the control and the sham-operation group, Brdu positive cells in Streptococcus pneumoniae meningitis rats were increased at 24 h post-infection, reached a peak at d5, then decreased, but still was greater than normal （P<0.05）.  Conclusion Streptococcus pneumoniae meningitis stimulated the proliferation of endogenous neural stem cells in the hippocampus of the rat brain.