Background Diffuse long coronary artery lesion remain difficult to treat in the era of drug-eluting stent (DES). The purpose of this study is to compare lesional outcomes of long and short stent implantation in one patient with two vessel disease. Materials and Methods From May 2005 to August 2010, a total of 121 patients with 242 lesions who had two vessel disease and performed percutaneous coronary intervention (PCI) with long and short DES for the two lesions were enrolled. Long segment stent was defined as implantation of DES over 50mm and short less than 50mm. Same kinds of DES were used in one patient. Angiographic follow-up was done at 8 months and clinical follow-up was done at 12 months. Study end-points were angiographic late loss, the rate of in-stent restenosis (ISR) defined as ��� 50% of a diameter stenosis and target vessel failure such as target lesion revascularization (TLR), target vessel revascularization (TVR) and lesion related myocardial infarction (MI). Results Stent length was 62.5짹12.5 mm in long lesion and 26.5짹8.9 mm in short lesion. Follow-up angiography was performed in 48.8% (59/121). In-stent restenosis was observed in 8.9% in long lesion and 3.4% in short lesion (p=0.124). Late loss at 8 months was statistically significant (0.71짹0.61 mm in long lesion vs. 0.42짹0.53 mm in short lesion, p<0.001). TLR and TVR were observed in 1.7% in long lesion and 0.8% in short lesion (p=0.561). Lesion related MI was not found both lesions. For 1 year, three cardiac deaths were observed due to two sudden deaths and 1 heart failure after index PCI. Conclusion Although lesion length contributes to the higher late loss, it didn���t affect on the cardiac outcomes. Larger study will be needed to evaluate this findings is related with clinical outcomes. Key Words: Long and short, Drug-eluting stent, Two-vessel disease