Objective: We analyzed the initial treatment of coronary artery disease, using information from the Korean Coronary Artery Disease Registry (KCAR) database. Methods and Results: Participating hospitals identify patients with a discharge diagnosis of coronary artery disease. Medical history, treatment, and outcome data are collected through review of medical records and entered into a database of KCAR. 2511 patients (mean age = 63.7짹10.4 years, 1581 males) were enrolled in this study. In clinical diagnosis, 24% of patients had stable angina, 36% unstable angina, 32% acute myocardial infarction, 7% variant angina. Of patients received antiplatelet agents, 80% aspirin, 64% clopidogrel, and 21% cilostazol. The beta-blocker was treated in 58% and calcium channel blocker in 35%. Of patients, 43% received angiotensin converting enzyme (ACE) inhibitors and 15% angiotesin receptor blockers (ARB). Stains were treated in 38% of patients. Other initial drugs were nitrate (59%) , nicorandil (8%), diuretics (12%), digoxin (2%), and warfarin (1%). Percutaneous coronary intervention (PCI) was applied in 64% of patients. Almost patient (92%) underwent stent implantation in PCI patients. Average doses of drugs appeared low for ACE inhibitors, ARBs, beta-blockers, and statins with recommendation. We examined the 671 patients (894 lesion, mean age= 61.3짹11.2 years, 482 males) who underwent stent implantation and follow-up coronary angiogram according to the initial medication. The patients were categorized into 4 groups; patients who received no statin and ARB (A, n=181), started statin (B, n=465, simvastatin = 20-40 mg, atorvastatin = 10-20 mg) or ARBs (C, n=54), and both statin and ARB (D, n=194) after stenting during follow-up time. ISR was lowest in group D (A, 30.3 %; B, 20.9 %; C, 19.4 %; D, 17.7 %, p<0.01). Conclusions: Combined treatment with statin and ARB could be used as a effective modality for preventing ISR in the patients with coronary artery disease. Conclusion: Initial management of patients with coronary artery disease is improving. Angiotensin receptor combined with statins are useful drugs for the prevention of in-stent restenosis.