Background: Acquired perforating dermatosis (APD) is a skin disorder occurring in patients with diabetes mellitus and/or chronic renal failure requiring dialysis. Objective : The purpose of this study was to clarify the clinical and histhopathological features of APD. Method: Twelve patients with APD who had biopsies done at Asan Medical Center were retrieved for this study. Clinical data and histopathologic specimens were reviewed. Results and Conclusion: 1. Sex ratio was 3:1 (9 male: 3 female) and mean age of onset was 52.1 years. 2. All patients had pruritic umbilicated papules with central keratotic plugs. The most predilection site was trunk. 3. Nine patients had an associated underlying non-insulin dependent diabetes mellitus 4. Skin lesions had developed on pre-dialysis in three patients, and after mean duration of 3.3 years on dialysis in remaining nine. 5. Histopathological examinations revealed the features of perforating folliculitis, Kyrle's disease or reactive perforating collagenosis. But we did not find any specimen resembling elastosis perforans serpiginosa. 6. It makes sense to designate the diseases as acquired perforating dermatosis rather than as one of the separate perforating diseases.