The incidence of multi-vessel disease was higher in patients with high TSH level (p=0.026). TSH level showed a significant correlation with age (r=0.109, p=0.044) and Gensini's score (r=0.117, p=0.045). The multivariate analysis revealed that age (OR 2.39, p=0.001), diabetes (OR 3.74, p=0.001), creatinine (OR 2.06, p=0.008), and smoking (OR 1.85, p=0.045) were independent predictors for significant coronary artery disease, but TSH level did not predict coronary artery stenosis.