BACKGROUND: The obesity paradox refers to lower mortality rates among overweight or obese individuals within certain populations. However, whether this paradox is applicable to patients undergoing percutaneous coronary intervention (PCI) remains unclear. METHODS: A total of 5,427 patients with coronary artery disease (CAD) who underwent successful PCI between 2005 and 2015 were enrolled. The association between body mass index (BMI) and future adverse cardiovascular events post PCI was analyzed. The study endpoints encompassed total cardiovascular (CV) events, including cardiac death, nonfatal myocardial infarction (MI), ischemic stroke, and hospitalization for congestive heart failure (CHF). RESULTS: Over an average follow-up period of 65.1 ± 32.1 months, 942 patients (17.4%) had CV events, including 200 CV deaths (3.7%), 294 acute MIs (5.4%), 111 ischemic strokes (2.0%), 469 CHF hospitalizations (8.6%), and 1,098 revascularizations (20.2%). A J-shaped relationship between BMI and future adverse events was observed, in which individuals with a BMI of 25.0-29.9 kg/m had significantly lower risks of total CV events [hazard ratio (HR) = 0.84, 95% confidence interval (CI) = 0.72-0.98], major adverse cardiovascular events (HR = 0.76, 95% CI = 0.63-0.93), acute MI (HR = 0.76, 95% CI = 0.58-1.00), and ischemic stroke (HR = 0.61, 95% CI = 0.39-0.95), compared to those with a BMI of 22.0-24.9 kg/m. CONCLUSIONS: We found a J-shaped relationship between baseline BMI and future adverse events in CAD patients undergoing PCI. Overweight individuals (BMI 25.0-29.9 kg/m) had the lowest future risk of total CV events compared to those with a normal BMI (22.0-24.9 kg/m).