Background : Intravascular ultrasound (IVUS) provide to better information than angiogram on the evaluation of lesion and procedural outcomes. Some studies have shown that IVUS-guided stenting improved angiographic restenosis as well as and clinical outcomes in bare metal stents era. The purpose of this study was to evaluate the influence of IVUS-guided stenting on angiographic restenosis rate and clinical outcomes when compared with angiogramphically- guided stenting. Methods : We retrospectively reviewed the medical records and angiography data of 1231 patients (with 1795 lesions) who underwent IVUS-guided or angiographically guided successful DES implantation in SNUH and SNUBH from Feb 2003 to May 2005. Patients were divided into IVUS-guided stenting (IVUS group; n= 359, M:F=261:98) and angiogram-guided stenting (angiogram group; n= 1436, M:F=934:502) group and six-month clinical and angiographic outcomes were evaluated. Results :The mean age of the patient was 63짹6 years-old and mean follow-up duration was about 6 month (186+/-62 day). There was no significant difference in baseline clinical and angiographical characteristics between the 2 groups except that IVUS-guided group had more bifurcation lesion than angiogramangiography-guided group.( p<0.01) IVUS-guided group (n= 359, M:F=261:98) showed larger size of post-stent minimal luminal diameter(3.09+/-0.42 mm vs.2.80+/-0.52 mm ,p<0.05) and stent diameter(p<0.01). Follow-up minimal luminal diameter was also larger in IVUS group (3.09+/-0.42 vs.2.80+/- 0.52mm p<0.05). The target lesion revascularization (TLR) (3.9 % vs. 4.94% , p=0.06) and major adverse cardiac events (death, MI, TLR ,MACE:5.0 vs.7.24% , p=0.06) tend to be lower in IVUS group than in angriogram groupangiography-guided group. Conclusion : Our results suggest that IVUS-guided stenting in DES implantation maybe improve angiographic and clinical outcomes in patients with DES implantation.