ObjectivesTo systematically review the efficacy and safety of mechanical thrombectomy for patients with acute ischemic stroke in different ages.MethodsPubMed, EMbase, The Cochrane Library, Web of Science, CNKI, and WanFang Data databases were electronically searched to collect randomized controlled trials (RCTs) and non-randomized controlled trials (non-RCTs) on the efficacy and safety of mechanical thrombectomy for patients with acute ischemic stroke in different ages from inception to August, 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies, then, meta-analysis was performed by using Stata 12.0 software.ResultsA total of 13 studies involving 2 995 patients were included. The results of meta-analysis showed that compared with the control group, patients aged 80 and above had no statistically significant difference in reperfusion success rates (OR=0.90, 95%CI 0.71 to 1.14, P=0.378), and incidence of symptomatic intracranial hemorrhage (OR=1.30, 95%CI 0.86 to 1.94, P=0.212), however, with higher incidence of arbitrary intracranial bleeding events (OR=1.61, 95%CI 1.28 to 2.04, P<0.001), 3-month mortality (OR=2.14, 95%CI 1.73 to 2.64, P<0.001) and lower good functional prognosis rate at 3 months (OR=0.46, 95%CI 0.30 to 0.71, P<0.001).ConclusionsCurrent evidence suggests that people aged 80 and above can obtain effective perfusion through mechanical thrombectomy, however, the incidence of postoperative adverse outcome events is higher and the prognosis is relatively poor. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify above conclusions.