Objective: To explore changes of neural stem cells (NSCs) following intracerebral hemorNYA's therapeutic mechanism Methods: Sixty rats were randomly divided into three groups, the sham operation control group, the ICH group and the NYA-treated group. Except those in the sham operation control group, all other rats were replicated to ICH models by stereotactical injection of collagenase type Ⅶ into their globus pallidus. After modeling, the rats in the NYA-treated group were administered with NYA at the given instead. The behavioral test was used to evaluate neurological deficit and immunohistochemical method was used to detect Nestin expression, the special marker for neural stem cells. Results: The ICH animals showed notable placing deficit in forlimbs from day 1 to day 28 after modeling. The deficit in the NYA-treated group was similar to that of the ICH group, but the former got recovered better than the latter from day 21 to 28, with significant difference shown (P＜0.05). Nestin-positive cells (N+ cells) could be seen around the hemotoma from day 2 on in the ICH group, the number of which gradually increased from day 4 to 7 ( P＜0.01) and reached the peak on day 14 (P＜0.05), but reduced significantly on day 28 (P＜0.01). Compared with that of the ICH group at the same time points, there was no significant difference in number of N+ cells in the NYA group on day 2 and 4, but it reached the peak earlier on day 7(P＜0.01), with the level significantly higher than that in the ICH group(P＜0.01), and this high level lasted to day 14. Conclusion: NYA could promote the recovery of behavioral deficit in collagenase type Ⅶ-induced ICH rats, and increase the number of nestin-immunoreactive NSCs, suggesting that its effect on NSCs may be one of its pharmaceutical mechanisms in treating ICH.