Background The lipid-lowering therapy by statins may stabilize and reduce coronary plaques. We compare the effect of strong or moderate statins on the coronary plaque characteristics by using 64-slice multidetector computed tomography (MDCT). Methods and Results We analyzed 13 subjects with non-calcified coronary plaques(NCP)as determined by MDCT. Pitavastatin(PTV:2mg/day)or pravastatin(PRA:10mg/day)were randomly administered. MDCT were performed at 0, 6 and 12 months after lipid-lowering therapy. In PTV group(n=6),CT density of NCP increased by 35.6 ± 28.8 HU after 6 months(p=0.037)and by 30.6 ± 29.8 HU after 12 months(NS).NCP area was decreased by 35.9 ± 15.2 % after 6 months and by 41.0 ± 16.5 % after 12 months(both P=0.001).In PRA group(n=7),CT density of NCP did not significantly increased after 6 months(NS)and after 12 months(NS).NCP area was not significantly decreased at 6 months(NS),but decreased by 23.1 ± 16.7 % at 12 months(P=0.001). Conclusions Serial CT angiography revealed that the regression of NCP occurs rapidly by strong lipid lowering therapy compared to the moderate statin therapy.