Aim To observe the vascular structures anomalies in posterior circulation ischemia patients by digital subtractions angiography (DSA), and to compare incidences of the posterior circulation vascular abnormalities of transient ischemic attack (TIA) patients with that of the posterior circulation ischemic infarction patients. Methods 397 patients were selected from Nanjing Stroke Registry Program from January 2004 to May 2008, and diagnosed as posterior circulation ischemia that had digital subtraction angiography examination at the same time. Results Posterior circulation vascular abnormalities were detected in 304 patients and 435 lesions, and there was no difference between the TIA and posterior circulation infarction patients (P>0.05). In the 78 patients without risk factor, there were 25 patients who had vertebral artery hypoplasia or posterior circulation variations. Conclusion The incidence of posterior circulation vascular anomalies in posterior circulation ischemia patients is high; there is no difference between the TIA and posterior circulation infarction patients. In patients without risk factor, the incidence of vertebral artery hypoplasia or posterior circulation variation is high.