Abstract Background Long-term prognosis after percutaneous coronary intervention (PCI), particularly non-target region stenosis, has not been well improved. Therefore, lifestyle modification should be considered along with medication to prevent the progression of coronary atherosclerosis. Particularly, the promotion of physical activity (PA) is recommended as a core intervention for secondary prevention because of its direct effects on coronary risk factors. However, the factors related to PA after PCI have not been fully investigated. Purpose To explore predictors of PA after discharge in patients underwent PCI. Methods We conducted a multicenter prospective cohort study. Participants were patients aged <75 years who underwent PCI. The main outcome was PA {step counts (SC) and a time of moderate-to-vigorous physical activity (MVPA)} measured for 7 consecutive days using an accelerometer at 3-month post discharge. We collected demographic data, comorbidities, medical history, laboratory data, and medications from medical record. In addition, severity of chest pain at the onset, physician's explanation regarding long-term prognosis, exercise environments, social support, work, lifestyle except exercise, self-efficacy for walking, difficulty in daily activities and depression were evaluated using questionnaires at discharge and 1-month post-discharge. The study participants were divided into two groups based on the median SC and MVPA at 3-month, and clinical characteristics were compared between the groups using χ2test or Mann Whitney U test. Then, multiple logistic regression analysis adjusted for age, gender, and diagnosis {stable angina or acute coronary syndrome (ACS)} was conducted with 3-month PA as dependent variable. Independent variables were those with a p<0.2 in the univariate analysis. In addition, the area under the curve (AUC) was calculated by receiver operating characteristic analysis to assess predictive accuracy of the regression model. Results We enrolled 313 patients [median age: 63 {inter-quartile range (IQR):56–67} years, women: 13.1%, ACS: 16.4%]. The median of SC and MVPA at 3-month were 6902 steps (IQR:5078–9095) and 16.2 min (IQR: 8.6–28.9), respectively. Predictors of SC at 3-month ≥the median were SC at 1-month (odds ratio 1.78, per 1000 steps/day; 95% confidence interval 1.51–2.09), hemoglobin (1.43, per 1g/dl; 1.10–1.86), body mass index (BMI) (0.87, per 1kg/m2; 0.82–0.99), use of β-blocker (0.49, 0.25–0.95), and self-efficacy for walking (1.06, per 1 point; 1.00–1.11). Predictors of MVPA ≥the median were MVPA at 1-month (5.66, per 10 minutes/day; 3.63–8.84), hemoglobin (1.57, per 1g/dl; 1.19–2.06), and BMI (0.85, per 1kg/m2; 0.76–0.94). The AUC of the regression model for SC and MVPA were 0.87 and 0.89, respectively. Conclusion PA after PCI could be predicted by modifiable factors with good predictive accuracy. The findings of this study suggest the possibility to develop tailored PA promotion program. Funding Acknowledgement Type of funding source: None