Background : Skin tags are benign fleshy or darker colored papillomatous dermal tumors locatei mostly in the neck, axill or groin. Recent reports on a possible association between skin tags and colonic polyps, however, caused interest in these henign tumors of the dermis, especially wite regarding to their frequercy. Objective : The purpose rate this study was to explore the clinical profiles of skin tags, the effect of obesity on the frequeny of skin tags and the association between skin tags and obesity in the normal population. We also tried to evaluate the usefulness of skin tags as a general marker for the presence of colonic piyps. Methods : The first, 524 unselected patients were examined. The patient material comprised of 240 males and 284 females. Each patient was inspected with regard to skin tags by a clermatolgist. 334 patients were classified into obese groups and nonobese groups and then we evaluated the relationship between skin tags and the degree of obesity. The second, ninety consecutive patients referred for coloniscopic evaluation were examined to determine the association between skin tags and colonic polps. Results : We found 22.9% of the males and 22.5% of the females to be skin tag carriers in the general population. We also noticed a steady increase of the frequency according to age eccept for the third decads. Of the skin tags found 51% were in the axillar region, 40% around the neck and 8% in the inguinal region. In the study for the relationship between skin tags and obesity, 44.9% of the obise patients and 23% of the nonobese patients were skin tag carriers(relative risk=1.95, p<0.05). In the study for the association between skin tags and colonic polyps in patients undergoing colonoscopic examination, 18 of patients with skin tags(45%) hnd colonic polyps and 11 of patients without skin tags(22%) had colonic polyps(relative risk=2.05, p<0.05). Conclusion : This study identified an obese group that are at risk of the developing skin tags. Consideration of skin tags as a marker for colonic polyps is likely to prove helpful. (Kor J Dermatol 1995;33(6): 1075-1078)