Background: Previous studies in animal model have demonstrated that neurotrophins were associated with functional outcome following stroke. However, the relationship between serum nerve growth factor (NGF) and functional outcome in stroke patients has not been explored. Our objective was to investigate the association between serum NGF concentrations at admission and functional outcome of patients at 3 month after stroke. Methods: One-hundred eight-five patients with acute ischaemic stroke were recruited in our study. Serum NGF concentrations were measured by ELISA at admission. The stroke severity at admission was assessed by the National Institute of Health Stroke Scale (NIHSS). The modified Rankin Scale (mRS) was used to assess the functional outcome of patients at 3 month after stroke. In addition, 100 healthy controls were recruited. Results: Serum NGF concentrations were higher in good functional outcome group (mRS score of 0-2) than that in poor functional outcome group (mRS score of 3-6) (9.51 +/- 2.33 vs. 8.12 +/- 1.61, P < 0.001). Meanwhile the serum NGF concentrations in healthy group were lower than that in acute ischemic stroke patient (7.17 +/- 1.49 vs. 9.15 +/- 2.24, P < 0.001). Moreover, our results demonstrated that high serum NGF con centrations (> 9.21 ng/l) were independently associated with the better functional prognosis at 3 months following the occurrence of stroke (OR 0.048, 95% CI 0.012-0.185, P < 0.001). Conclusions: High concentrations of serum NGF at admission may predict good functional outcome of patients a 3 months after acute cerebral ischemia stroke.