Aim To explore the relationship between serum bilirubin and the severity of coronary artery lesion, prognosis in patients with angina. Methods This study included 486 continuous angina patients meeting the conditions from January 1,3 to December 1,5. The subjects included 292 males and 194 females, with an average age of (61.4±13.2) years. On the day before discharge, fasting venous blood was drawn to detect total bilirubin. Coronary angiography was retrospectively analyzed and the coronary artery lesions were scored using the SYNTAX scoring system. In this study, prospective follow-up was performed. The initial event was PCI and the end event was major adverse cardiovascular events (MACE). The follow-up deadline was December 1,7. Multivariate logistic regression was used to analyze the relationship between serum bilirubin and SYNTAX scores. The Kaplan-Meier method was used to estimate the survival rate. The log-rank test was used to compare the two survival curves. The relationship between serum total bilirubin and MACE was analyzed by multivariate Cox proportional hazards regression. Results Multivariate logistic regression analysis showed that male, age, type 2 diabetes mellitus, low density lipoprotein cholesterol (LDLC), high density lipoprotein cholesterol (HDLC) and bilirubin were independent factors for the moderate-to-high SYNTAX score. MACE occurred in 38 patients of the low bilirubin group and in 25 patients of the hyperbilirubin group. There was significant difference in MACE-free survival curve between the two groups (χ²=4.785, P=0.029). Multivariate Cox regression analysis showed that male, age, bilirubin and SYNTAX scores were independent factors for the occurrence of MACE. Conclusion Serum bilirubin is an important factor affecting the degree of coronary artery lesion and long-term prognosis in PCI patients with angina.