Abstract: Objective To estimate the predictor application of the plasma brain natriuretic peptide level in acute ischemic stroke patients by investigating the relationship between the brain natriuretic peptide level with neural function recovery degree of the 3 months' phase.Methods According to the diagnostic criteria stipulated in the “Chinese acute ischemic stroke diagnosis and treatment guidelines 2010 ”, we prospectively enrolled 88 patients with AIS within 24 hours of onset and measured the plasma brain natriuretic peptide, thus comparing the good recovery group and the bad recovery group.Results There was a significant correlation found between neural function recovery degree of the 3 months' phase and the plasma brain natriuretic peptide level, infarction volume in patients with acute ischemic stroke(P＜0.001). The plasma brain natriuretic peptide levels on admission were significantly higher in the bad group than in the good group(884.75±330.07 pg/mL vs. 263.27±281.89pg/mL, P＜0.001). The predictor level, sensitivity and specificity of the plasma BNP level in bad neural function recovery of the 3 months' phase showed brain natriuretic peptide level of≥366.40pg/mL, 96.00 % and 76.19 %.Conclusion The plasma brain natriuretic peptide level on admission can predict the neural function recovery degree of the 3 months’ phase in patients with acute ischemic stroke.