Abstract: Objective?To investigate the effect of insulin-like growth factor Ⅰ (IGF-Ⅰ) on the anti-apoptosis of neural precursor cells. Methods?Rat neural precursor cells (Ge6) were used as experiment object. 10 ng/mL IGF-Ⅰ were applied to cultured Ge6 differentiated 2 d, 4 d, 6 d and the untreated cells as control. Quantitative reverse transcriptase PCR (qRT-PCR) was used to detect the effect of the IGF-Ⅰ on caspase-3 mRNA in the Ge6 of different groups and Immunofluorescent staining were applied to obverse the positive rate of caspase-3. Results?qRT-PCR demonstrated that caspase-3 mRNA level of experimental group decreased compared to that of the control group, the differences between experimental group cultured for 4 d (2.007±0.297), 6 d (1.194±0.244) and the control group cultured for 4 d (5.530±1.027), 6 d (5.371±0.513) were statistically significant (P<0.05). Immunofluorescent staining indicated that the caspase-3 positive rate of experimental group cultured for 2 d, 4 d and 6 d were reduced compared to that of the control group, the differences between experimental group cultured for 4 d (3.5%±0.2%), 6 d (5.1%±0.1%) and the control group cultured for 4 d (7.0%±0.5%), 6 d (7.4%±0.4%) were statistically significant (P<0.05). Conclusion?IGF-I plays an anti-apoptosis role on neural precursor cells.