OBJECTIVE; The aim of this study was to compare the six months angiographic results of the side branch(SB) in bifurcation lesions treated single Drug-Eluting Stent(DES) with and without kissing balloon technique. METHOD; We analyzed consecutive 60 patients(male % 65, mean age; 62짹10 years) who underwent percutaneous coronary interventions(PCI) for bifurcation lesions using DES and angiographic follow-up. We divided into single DES with kissing balloon technique(Group A, n=28) and without final kissing balloon technique(Group B n=32). Each technique was decided by operators��� discretion. RESULT; The demographic data was similar in both groups. There were no significant differences regarding bifurcation lesion type[true bifurcation %; 69 vs. 64 p=0.251], the reference diameter(RD) of pre-PCI main branch [3.19짹0.31mm vs. 3.03짹0.37mm, p=0.67], side branch RD[2.54짹0.28mm vs. 2.41짹0.35, p=0.127]. However, diameter stenosis of pre-PCI SB was significantly higher in group A (58.7짹24.6% vs. 39.6짹22.9%, p=0.03) and final diameter stenosis of SB was significantly higher in group B (25.9짹19.5% vs. 43.0짹20.4%, p=0.02). In follow-up angiography (mean duration; 192짹15 d.), there was no differences occlusion rate of SB vessels[3.2% vs. 6.2%, p=0.15], restenosis rate of main branch and target vessel revascularization [10.7% vs. 3.1% , p=0.331], late loss of SB vessels [0.28짹0.42mm vs. 0.25짹0.34mm, p=0.795] and TIMI3 flow rate (92.8% vs. 93.7% p=0.467). CONCLUSION; There were similar angiographic follow-up results of TIMI flow and late loss between single DES implantation with and without kissing balloon technique.