Abstract: Objective:To explore the factors influencing the clinical prognosis of patients with top of the basilar syndrome(TOBS).Methods:A total of 50 patients with TOBS were divided into the favorable outcome group(MRS 0-3) and unfavorable outcome group(MRS 4-6) according to the MRS after 30 d of onset.The general information on admission,imaging findings,National Institutes of Health Stroke Scale(NIHSS) score and Glasgow Coma Scale(GCS) score between two groups were compared.Results:The difference of the pathogenesis between two groups was statistically significant(P<0.01),and the embolism was the main pathogenesis in unfavorable outcome group(82.1%).The difference of the lesion location between two groups was statistically significant(P<0.01),and the mix lesion was the main in unfavorable outcome group(71.4%).The NIHSS score and GCS score in unfavorable outcome group were significantly higher and lower than that in favorable outcome group,respectively(P<0.01).Conclusions:The clinical prognosis in patients with embolism,upper and lower tentoriums cerelelli involved are poor.The diagnosis and treatment plan should be optimized to reduce the fatality rate of TOBS handicap.The combined score of NIHSS and GCS may effectively evaluate the disease and prognosis of TOBS.