Purpose: To evaluate the safety and efficacy of Enterprise stent in the treatment of symptomatic complex intracranial atherosclerotic stenosis.Methods and materials: 20 complex cases among 53 patients with symptomatic ischemic stroke who were treated with balloon angioplasty and enterprise stents in Department of Neuro-interventional Radiology,The First Affiliated Hospital of Zhengzhou University from Jan.2014 to Dec.2017 were retrospectively enrolled in this study.Diagnostic criteria for complex intracranial atherosclerotic stenosis were as follows: 1) intracranial atherosclerotic stenosis was ≥70％ confirmed by digital subtraction angiography (DSA) using the formulas described by the Warfarin Aspirin Symptomatic Intracranial Disease (WASID) method;2) length of lesion was ＞10 mm.Basic characteristics of target lesions,technical success rate,perioperative safety,follow-up outcomes were investigated.Results: 20 patients were enrolled in this study,including 15 males and 5 females from 44 to 70 years old with an average age of 57.20 ± 9.25.20 lesions were treated with 20 enterprise stents.The average preoperative and postoperative residual stenosis was reduced from (77.45 ± 8.44)％ to (24.89 ± 16.61)％.The successful rate of operation was 100％.Among the perioperative complications,only 1 case (5％) experienced perforating branch event.The average clinical follow-up period was 13.15 ± 11.33 months (time range: 5-38).There were no ischemic events,no bleeding events and no various causes of death during the follow-up period.8 lesions (40.0％) underwent DSA follow-up examinations and 12 lesions (60.0％) were checked by CT angiography during the follow-up period.3 lesions (15.0％) developed ISR without any cerebral ischemia symptoms.Conclusion: This retrospective,single-center study suggests that enterprise stent is effective in the treatment of symptomatic complex intracranial atherosclerotic stenosis with less perioperative complications.Prospective,multicenter,randomized controlled trials are expected.