Background: This study was designed to evaluate the effects of rosuvastatin, ramipril and combined therapy on lipoprotein levels, inflammatory markers and plaque volume measured by intravascular ultrasound (IVUS) in patients with intermediate coronary artery stenosis, baseline total cholesterol level below 250mg/dL. Methods: Subjects were randomly assigned to 3 treatment groups (rosuvastatin groups (S); 20 mg/day, ramipril group (A); 10 mg/d, combined group (A); rosuvastatin 20mg+ramipril 10mg/day). Total 52 patients (S=21, C=18, T=13), 60 intermediate coronary lesions (S=24, C=22, T=14) were completely taken follow-up IVUS study after 9 months therapy. Results: Rosuvastatin alone or combined therapy significantly reduced total cholesterol and LDL cholesterol levels compared to ramipril alone (all p<0.001). All 3 treatments groups significantly reduced hsCRP levels relative to baseline measurements. However, the magnitude of reduction among these 3 therapies was not significant (p=0.44) The changes of fasting glucose and insulin among 3 groups were not different (p=NS). All 3 treatment groups significantly reduced normalized-total atheroma volume (TAV) (all p<0.05). However, percent atheroma volume (PAV) were not significantly changed in all 3 groups. Of interest, only combined therapy significantly reduced TAV and PAV in 10 mm subsegment with greatest disease (p<0.001, p=0.04, respectively). The changes of atheroma volume among 3 groups were not significantly different. Conclusions: Only combined therapy with rosuvastatin and ramipril significantly reduced TAV and PAV in 10 mm subsegment with greatest disease. More large scaled study are warranted in the future.