Objective To study the effects of fimbria fornix transection and intraventricular injection of nerve growth factor(NGF) on the proliferation and differentiation of endogenous neural stem cells (NSCs)in the hippocampus into neurons. Methods Twelve SD rats were divided into the treatment group and control group randomly, six rats in each group. The right fimbria fornix of rats were transected. NGF and artificial cerebrospinal fluid was injected into the lateral ventricle of rats in the treatment group and control group respectively immediately and on the 2nd and 4th day after transection. Bromodeoxyuridin (BrdU) was injected intraperitoneally twice per day from 3 to 7 days after operation. On the 28th day after operation, the brains were perfused for fixation and frozen section. BrdU/NF-200 doublelabel immunofluorescence was used to detect the proliferation and differentiation of NSCs into neurons. Results In dentate gyrus，the number of BrdU positive cells in the transection side was much more than those of normal side both in the treatment group and the control group, and the BrdU positive cells in treatment group were more than those of control group both in the transection side and normal side; The number of BrdU/NF-200 double labeled neurons was the most in the transection side of the treatment group, less in normal side of treatment group and transection side of the control group, but absent in the normal side of the control group.Conclusion Fimbria fornix transection could cause endogenous neural stem cells in the hippocampus proliferate and differentiate into