Cystatin-C, a marker of mild renal dysfunction, has been reported to be associated with cardiovascular diseases including vasospastic angina (VSA). We aimed to investigate the impact of cystatin-C level on the prevalence and angiographic characteristics of VSA in Korean patients.A total of 549 patients in the VA-KOREA (Vasospastic Angina in KOREA) registry who underwent ergonovine provocation tests were consecutively enrolled. Estimated glomerular filtration rate (eGFR) and levels of serum creatinine (Cr) and cystatin-C were assessed before angiography.The patients were classified into two groups: the VSA group (n = 149, 27.1%) and the non-VSA group (n = 400). Although eGFR and Cr levels were similar between the two groups, the VSA group had a significantly higher level of cystatin-C (P < 0.05). A high level of cystatin-C (second tertile, hazard ratio 1.432; 95% confidence interval [1.1491.805]; P = 0.026, third tertile, 1.947 [1.132-2.719]; P = 0.003) and current smoking (2.710 [1.415-4.098]; P < 0.001) were independently associated with the prevalence of VSA. Furthermore, the highest level of cystatin-C (> 0.96 ng/mL) had a significant impact on the incidence of multivessel spasm (2.608 [1.061-4.596]; P = 0.037).A high level of cystatin-C was independently associated with the prevalence of VSA and with a high-risk type of VSA in Korean patients, suggesting that proactive investigation of VSA should be considered for patients with mild renal dysfunction indicated by elevated cystatin-C.