Idiopathic Atrophoderma of Pasini and Pierini (IAPP) is a rare, exclusively cutaneous disease. It is more frequent in females, with incidence peak in the second and third decades of life. The etiopathogenesis remains unknown. IAPP most commonly affects the back, abdomen and proximal regions of the limbs. Lesions may be rounded, oval or circular; single or multiple. The evolution is variable and the course is initially progressive. Collagen changes such as atrophy, thinning, condensation and sclerosis may be observed in the papillary dermis. This paper describes a case of Idiopathic Atrophoderma of Pasini and Pierini with histopathologic findings.