Background: Stenting in proximal LAD including ostial lesion is known to be associated with suboptimal success and high target vessel revascularization (TVR) rate but drug-eluting stent (DES) implantation for LAD ostial lesion has shown significantly reduced restenosis and late event rate. However, the impact of DES on RCA ostial lesion is not reported yet. Methods: Among the 66 patients (pts; male 38, mean age 62.1짹10.6 years) with 85 ostial lesion underwent standard PCI with DES, the 6-month clinical and angiographic outcomes of 13 pts with 16 RCA ostial lesions (RCA ostial group) were compared with those of 53 pts with 69 non-RCA ostial lesions (Non-RCA ostial group). Results: Baseline characteristics were similar between the two groups. Among the non-RCA ostial group, left main was 13.0% (9/69), LAD 52.2% (36/69) and LCX 34.8% (24/69). DES diameter, length and DES type (Cypher or Taxus) were similar between two groups. Periprocedural and in-hospital complications were similar between two groups. At 6 months, binary restenosis, restenosis % and major adverse cardiac events (MACE) including death, myocardial infarction and revascularization were numerically higher in non-RCA ostial group but were not statistically different between two groups (Table). Conclusions: Treatment of RCA ostial lesion with DES appears safe and feasible with low procedural and in-hospital complications. Six-month clinical and angiographic follow-up showed sustained benefit of DES on the RCA ostial lesions with low subsequent revascularization compared with the non-RCA ostial lesion.