Objective Delayed cerebral ischemia (DCI) seriously affect and lead to aneurismal subarachnoid hemorrhage(aSAH) with poor prognosis. From the aspectof hemodynamics, three-dimension arterial spin labeling(3D ASL) early predicts occurrence of cerebral ischemia, to guide the preventive treatment of aneurysmal subarachnoid hemorrhage patients, and to improve prognosis. Methods Totally 30 cases with SAH were respectively analyzed, all patients underwent magnetic resonance on days 3～14 d, assessing prognosis of patients with Modified Rankin scale (MRS ).In addition, during the same period, 10 cases of aneurysm no-repture hemorrhage patients were selected as control group. All patients were divided into DCI group and non-DCI group. Analyze the relevance of hemodynamic changes of patients with aSAH and early prognosis. Results Differences between 3 groups in degree of cerebral blood flow perfusion abnormalities, and the difference is statistically significant(Chi-Square=17.540, P=0.000). The degree of cerebral perfusion and mRS score was significantly positive correlation(r=0.955, P=0.000). Conclusion The occurrence of DCI was associated with a significant early prognosis. 3D ASL, may be an early useful tool to early prognosis evaluation.