We report a case of secondary anetoderma due to pilomatricoma. A 15-year-old girl presented with a soft, 1.5 × 1.5cm in size, atrophic, pinkish and bulged-out lesion overlying the palpable subcutaneous mass on the left upper arm for several months. Histologic examination revealed the reduced number of dermal elastic fibers overlying a typical pilomatricoma.