Objective:To explore risk factors of in-stent restenosis (ISR) after vertebral artery stenting (VAS) in patients with ischemic cerebrovascular disease.Methods:Case-control studies and cohort studies on risk factors for ISR after VAS in patients with ischemic cerebrovascular disease were searched from CNKI, VIP, Wanfang, Chinese Biomedical literature Database, PubMed, Embase and Cochrane Library. The retrieval time limit was the establishment of each database until May 31, 2021. Two researchers screened the literature and extracted relevant data. Newcastle-Ottawa Scale (NOS) was used to evaluate quality of the literature and RevMan 5.3 software was used for meta-analysis.Results:A total of 30 studies were included. Meta-analysis results showed that smoking [ OR=3.76, 95% confidence interval ( CI) : 2.43-5.82, P<0.01], diabetes ( OR=2.95, 95% CI: 2.15-4.06, P<0.01) , hypertension ( OR=2.55, 95% CI: 1.50-4.34, P=0.006) , hyperlipidemia ( OR=7.12, 95% CI: 3.46-14.68, P<0.01) , coronary heart disease ( OR=3.06, 95% CI: 1.10-8.47, P=0.03) , homocysteine ( OR=2.36, 95% CI: 1.30-4.27, P=0.005) , clopidogrel drug-related gene ( CYP2C19) mutation ( OR=3.04, 95% CI: 1.63-5.68, P=0.005) , lesion vessel diameter ( OR=3.43, 95% CI: 1.30-9.05, P=0.01) , residual stenosis ( OR=6.08, 95% CI: 3.28-14.07, P<0.01) ) , stent type ( OR=2.26, 95% CI: 1.18-4.36, P=0.01) , stent length ( OR=3.52, 95% CI: 2.34-5.30, P<0.01) were associated with ISR after VAS operation in patients with ischemic cerebrovascular disease. Conclusions:Postoperative smoking, history of diabetes mellitus, history of hypertension, history of hyperlipidemia, history of coronary heart disease, high level of homocysteine, CYP2C19 mutation, shorter lesion vessel diameter, postoperative residual stenosis, use of bare metal stents and longer stent length are risk factors for ISR after VAS in patients with ischemic cerebrovascular disease. Clinical medical staff should adjust the follow-up time of postoperative patients according to risk factors and formulate individualized strategies to prevent the occurrence of ISR.