The purpose of the trail is to determine whether DCB is superior to conventional balloon in treating cerebral atherosclerotic stenosis

Incsion Criteria:

• Age 18 to 80 years old at informed consent signing.
• Symptomatic atherosclerotic stenosis of cerebrovascular arteries with ≥70% stenosis.
• Medication ineffective.
• modified Rankin Scale(mRS) score≤2.
• The subject or guardian is able to understand the purpose of the study, is willing to participate and has given written informed consent.

Exclusion Criteria:

• History of acute ischemic stroke within 2 weeks;
• Stenosis due to non-atherosclerotic lesions such as arterial dissection, Moya-Moya disease and vasculitic disease;
• Target vessels complete occlusion or with thrombus in target vessels;
• Target vessel with severe calcification or distortion that making interventional device is difficult to place;
• History of stenting in the target artery;
• Target vessel restenosis following stenting or balloon angioplasty;
• Combined with other lesion with ≥70% stenosis in target vessel.
• Residual stenosis ≥50% or vessel dissection with obvious blood flow restriction occurs after predilation.
• Combined with intracranial tumour, arteriovenous malformation or aneurysm of the target vessel.
• History of intracranial hemorrhage within 90days.
• Presence of severe systemic diseases that cannot tolerate surgery, such as severe liver and kidney dysfunction;
• Contraindication to the use of anticoagulants and antiplatelet agents, such as sllergy to anticoagulants and antiplatelet agents, active bleeding or coagulation disorders;
• Allergic to contrast agents or rapamycin;
• Pregnant or lactating women;
• Participating or intending to participate in any other drug/device clinical trials;
• Life expectancy <1 year;
• Any other conditions that the investigator deems the patient unsuitable for enrollment.