The risk factors for post-procedural events after carotid artery stenting (CAS) have not been well established. The aim of this study was to investigate the association between metabolic syndrome (MetS) and the risk of post-CAS complications. A total of 358 consecutive patients who underwent CAS were enrolled in this prospective study. Patients' demographic data, clinical characteristics, and complications after CAS within 30 days were recorded. Logistic regression analysis was performed to identify possible risk factors for post-procedural complications after CAS. The incidence of complications after CAS within 30 days was 7.0%. Logistic regression analysis identified the following as independent risk factors for 30-day transient ischemic attacks, stroke, myocardial infarction, and death after CAS: metabolic syndrome (OR = 2.31, 95% CI 1.91-3.01, P = 0.004), diabetes (OR = 2.24, 95% CI 1.74-2.76, P = 0.026), symptomatic patient (OR = 1.73, 95% CI 1.23-3.05, P = 0.011), and age (OR = 1.87, 95% CI 1.35-2.57, P = 0.042). Among the components of MetS, central obesity (OR = 2.21, 95% CI 1.24-2.63, P = 0.006), low high-density lipoprotein cholesterol (HDL-C) (OR = 1.66, 95% CI 1.34-2.27, P = 0.022), and high fasting plasma glucose (OR = 2.32, 95% CI 1.85-2.74, P = 0.003) were associated with increased risk of 30-day complications after CAS. This present study suggests that patients with metabolic syndrome have significantly increased risk of complications after CAS within 30 days. Moreover, MetS patients with central obesity, high fasting plasma glucose, or low HDL-C have significantly increased risk of complications after CAS within 30 days.