Vertebrobasilar dolichoectasia (VBD), a rare posterior circulation vascular variant disease, is an important risk factor for many acute cerebrovascular diseases. An insufficient understanding of VBD often leads to misdiagnose. Two cases of VBD that were initially diagnosed as posterior circulation watershed infarction are reported here. Absence of common causes of stroke including hypoperfusion, blood system diseases, carotid and aortic dissection, and eosinophil elevation, the symptoms of the 2 patients met the diagnostic criteria of VBD. Both patients displayed symptoms that were in line with the Traditional Chinese Medicine (TCM) syndrome pattern of "Qi deficiency and blood stasis". Accordingly, they were comprehensively treated with Supplementing Qi and activating blood circulation method. The clinical manifestations of the 2 patients were remarkably improved and no recurrence of watershed infarction was found in a 1-year follow-up. A detailed medical history and laboratory examination are capable of improving diagnostic accuracy of VBD. TCM treatment based on syndrome identification might be a promising candidate for VBD management.