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Introduction: Vertebral Artery Stump Syndrome (VASS) has previously been reported as a mechanism of embolism to posterior circulation (PC) that is due to flow stagnation caused by VA origin occlusion. We report the efficacy of endovascular treatment (EVT) for VASS including the novel method of approach. Methods: We retrospectively investigated 1381 consecutive cases of ischemic stroke treated in our institution. Diagnosis of VASS was performed on cases of embolism in PC area alone with VA proximal occlusion accompanied by distal flow stagnation and without other embolic sources. EVT was performed on cases in which infarction recurred in medical treatment resistance or in which BA acute occlusion was present. Approach of EVT was selected depending on state of the case. In addition to conventional methods of parent artery occlusion (PAO) and angioplasty by antegrade approach (AA), we devised and performed a novel method of approach for angioplasty by retrograde approach (RA) via collateral circulation or contralateral VA. Results: Embolism of the PC area alone was 323 cases, 10 of which (3.1%) were diagnosed as VASS. EVT was performed on 6 cases. No symptomatic complications due to the procedure were observed. In all cases, recurrence of infarction was not observed, but retreatment was required in 1 case. The treatment contents were as follows: 1 case of PAO, 4 cases of angioplasty by AA, and 2 cases of angioplasty by RA (via deep cervical artery; 1, via contralateral VA; 1). Conclusion: There are several reports of anticoagulant therapy and EVT as a treatment for VASS, but it has not been established. Since EVT can be performed relatively safely, it may be the first choice for treatment. Appropriate approach should be considered according to the condition of the lesion. In occlusion of VA, the orifice of VA is often flattened, in which case AA is difficult. RA to occluded vessels, which is a common procedure in cardiovascular vessels, may be applicable to the neurovascular region.