Background: The pathogenesis of UNT is still unknown.There have been only case reports and case series of bilateral nevoid telangiectasia (BNT) thus far. Objectives: To assess different demographic, clinical and laboratory features between unilateral and bilateral nevoidtelangiectasia. Methods: Nevoid telangiectasia cases diagnosed between January 2004 and August 2014 at Seoul National University (SNU) Hospital and SNU Boramae Hospital were divided intotwo groups (unilateral and bilateral) based on clinical presentation (UNT:12, BNT:12). Between the two groups, we compared the age at visit, age of onset, underlying diseases, and laboratory findings. Results: The age of onset was much later in BNT, firstappearing at 55.6±4.1 years in contrast to 15.2±5.6 of UNT (p<0.001). Significantly higher proportion (91.7%) of females had UNT, whereas most (83.3%) of BNT patients were male (p=0.001). Furthermore, none of the UNT patients had any laboratory abnormalities or underlying diseases, whereas in BNT group 5 patients were HBV carriers (p=0.014), 2 had fatty liver, 2 had diabetes, 2 had liver cirrhosis, and 1 had hepatocellular carcinoma with liver function abnormalities (p=0.001 with any liver diseases). Conclusion: BNT may be more common than previouslythought, and it may have different pathogenesis compared with UNT. We propose that in bilateral forms work-up for underlying systemic diseases should be performed.