Objective To investigate the risk factors of heart failure in patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI). Methods A total of 520 patients undergoing PCI due to ACS in our hospital from 2009 to 2012 were enrolled in this study. Then they were divided into heart failure group (n＝67) and control group (n＝453) according to the emergence of heart failure after PCI. Their clinical data were collected and retrospectively analyzed. The numbers of patients with histories of hypertension, diabetes, smoking, old myocardial infarction or prior history of heart failure were calculated. Their coronary angiography images, operation time, amount of contrast agent, and the levels of blood glucose, blood lipids, and other blood test indicators during hospitalization were analyzed between the 2 groups. Results Sixty-seven patients had heart failure after PCI. Compared to control group, they suffered a longer hospitalization and significantly higher mortality (P＜0.05). What’s more, the heart failure group had longer operation time, larger amount of contrast agent, higher ratio of diabetes, more lesions in anterior descending artery, less incidence of unstable angina pectoris, and higher incidence of myocardial infarction than the control group (P＜0.05). Blood test showed that the levels of low-density lipoprotein cholesterol, creatinine and uric acid, and the white cell count were significantly higher in the heart failure group than in the control group (P＜0.05). Linear logistic regression analysis showed that age, left anterior descending artery lesion, white blood cell count, uric acid level were the high risk factors of heart failure after PCI. Conclusion Elderly patients with anterior descending artery lesions combined with higher white blood cell count and uric acid level are in higher risk of heart failure after PCI.