Objective:To explore the efficacy of cerebral vasospasm model established by brief double blood injection in cisternal cisteria.Methods:Twenty-five SD rats were randomly divided into sham-operated group, group of 1 d after subarachnoid hemorrhage (SAH), group of 3 d after SAH, group of 5 d after SAH, and group of 7 d after SAH ( n=5). Autologous blood (0.2 mL, obtained by caudal artery puncture) was directly injected into the atlanto-occipital membrane and repeated 48 h after that to establish cerebral vasospasm model. Neurological impairment was evaluated by modified Neurological Severity Score (mNSS). Diameter and cross-sectional area of the basilar artery (BA) were detected by HE staining. Differences of body mass before modeling, body mass between the 2 blood injections, mNSS scores, and diameter and cross-sectional area of BA were compared among groups. Results:(1) Body mass before modeling was not significantly different among the 5 groups ( P>0.05); differences of body mass between the 2 blood injections in the group of 1 d after SAH, group of 3 d after SAH, group of 5 d after SAH, and group of 7 d after SAH were significantly greater than those in the sham-operated group ( P<0.05). (2) The mNSS scores in the group of 1 d after SAH, group of 3 d after SAH, group of 5 d after SAH, and group of 7 d after SAH were significantly higher than those in the sham-operated group ( P<0.05). (3) BA diameter in the group of 3 d after SAH and group of 7 d after SAH was significantly shorter than that in the sham-operated group, and that in the group of 7 d after SAH was significantly shorter than that in the group of 1 d after SAH and group of 5 d after SAH ( P<0.05). BA cross-sectional area in the group of 1 d after SAH, group of 3 d after SAH, group of 5 d after SAH and group of 7 d after SAH was significantly smaller than that in the sham-operated group, and that in the group of 7 d after SAH was significantly smaller than that in the group of 1 d after SAH, group of 3 d after SAH and group of 5 d after SAH ( P<0.05). Conclusion:Compared with other traditional models, cerebral vasospasm model established by brief double blood injection in cisternal cisteria has advantages of simplified operation, short modeling time, and minimal invasion; model of 7 d after autologous blood injection enjoys optimal.