Background: ApoB/ApoA-I ratio is known to be associated with cardiovascular complications of general populations. However, there have been limited data whether the association of Apo B/Apo A-I ratio and clinical outcomes of patients (pts) undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DESs). Methods: The study population consisted of 415 consecutive pts underwent PCI with DESs enrolled from 2004 to 2008. 2-year cumulative major clinical outcomes of pts with high ApoB/ApoA-I ratio group (���0.8, n= 102) was compared with those of low ApoB/ApoA-I ratio group (<0.8, n=313). Results: The baseline clinical characteristics including gender, age, diabetes, hyperlipidemia, chronic kidney disease, smoking were similar between the two groups except acute myocardial infarction (AMI), hypertension (HTN), total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, Lipoprotein(a) [Lp(a)] level (table). 2-year major clinical outcomes were not different between the two groups except total MACE (Table). When adjusted by AMI, HTN, total MACE was a trend to increase in high ApoB/ApoA-I ratio group than low high ApoB/ApoA-I ratio group (p= 0.099). Conclusions: In our study, high level of ApoB/ApoA-I ratio in pts undergoing PCI with DESs may be associated with total MACE up to 2 year follow-up, as compared to those of control group.