Infantile perianal pyramidal protrusion(IPPP) is a benign mass which is characterized by solitary pyramidal protrusion and typical localization on the perineal or perianal area. In 1996, Kayashima et al first used this name. IPPP has been divided into three categories based on the history and clinical findings at presentation: constitutional IPPP, functional IPPP, and IPPP associated with lichen sclerosus et atrophicus. Two cases of IPPP have been reported in Korean dermatologic literature. A 2-year-old girl presented with a month history of a smooth linguiform protrusion on anterior to the anus. She had suffered from painful defecation but had no history of constipation. There was no remarkable medical history and family history. We performed shave biopsy and CO2 laser ablation. Histopathologic examination showed epidermal hyperplasia, dermal edema, and hemorrhage with inflammatory cell infiltration in dermis. In general, IPPP shows a benign clinical course. IPPP can be misdiagnosed as sexual abuse, anogenital warts or hemorrhoid due to its location on the perineal area. Therefore physician’s awareness of IPPP is important in its differential diagnosis from other disease.