Abstract: Objective:To evaluate systematically the efficacy and safety of nimodipine injection in the treatment of patients suffering from cerebral vasospasm after subarachnoid hemorrhage.Methods:By overall collecting the related literature of controlled clinical trials about nimodipine injection for the treatment of cerebral vasospasm after subarachnoid hemorrhage from 1994 to 2007,Meta analysis was conducted by means of Review with Manager 4.2 software.Results:The homogenecity test of 16 selected clinical research showed that they had homogenicity (P>0.05).The result of Meta analysis showed that the rate of cerebral vasospasm and mortality rate after subarachnoid hemorrhage was much lower in nimodipine group than the control group (P<0.000001).The rate of rehaemorrhagia had no difference between the two groups (P=0.17).Conclusions:The evidence available shows that nimodipine is effective and safe in the treatment of cerebral vasospasm after subarachnoid hemorrhage and does not raise the risk of re-hemorrhage.