Objectives: The relation between positive remodeling (PR) of coronary artery and plaque composition has been studied only in relatively small number of study population or non-culprit lesion. We sought to evaluate the association between coronary plaque composition and coronary artery remodeling in relatively large number of culprit lesion. Methods: Study population consisted of 332 consecutive patients (mean 61.6짹12.2 years old, 233 males) underwent intravascular ultrasound-virtual histology (IVUS-VH) examination. The remodeling index (RI) was calculated as the lesion external elastic membrane (EEM) area divided by the average reference EEM area. Results: The lesions with PR (RI >1.05, n=100, mean RI=1.18짹0.12) had higher fibrous volume/lesion length (3.79짹2.12mm³/mm vs. 3.02짹1.79mm³/mm, p=0.003) and necrotic core volume/lesion length (1.25짹0.89mm³/mm vs. 0.90짹0.68mm³/mm, p=0.001) than those with negative remodeling (NR, RI<0.95, n=139, mean RI=0.82짹0.11). At minimal luminal area site, the lesions with PR had higher fibrous area (5.73짹3.17mm² vs. 3.57짹2.28mm², p<0.001), dense calcified area (0.73짹0.68mm² vs. 0.47짹0.44mm², p<0.001), and necrotic core area (1.94짹1.33mm² vs. 1.07짹0.91mm², p<0.001) than those with NR. RI showed significant positive correlation with fibrous volume/lesion length (r=0.177, p=0.001), necrotic core volume/lesion length (r=0.185, p=0.001), fibrous area (r=0.349, p<0.001), fibrofatty area (r=0.116, p=0.036), dense calcified area (r=0.237, p<0.001), and necrotic core area (r=0.325, p<0.001). Multivariate analysis showed that the independent factors for PR were fibrous area (beta=0.889, 95% confidence interval (CI); 0.196~1.558, p<0.001) and necrotic core area (beta=0.172, 95% CI; 0.028 `0.224, p=0.012) at minimal luminal area site. Conclusions: This study suggests that positive vascular remodeling in culprit lesion is associated with fibrous area, which is main composition of plaque, and necrotic core area, which is a characteristic of complex plaque.