Papillon-Lefevre syndrome is an extremely rare autosomal recessive genodermatosis characterized by diffuse palmoplantar keratoderma and severe early-onset periodontitis. The malignant cutaneous neoplasms developed within the hyperkeratotic lesions of Papillon-Lefevre syndrome patient are exceptional, and the association of Papillon-Lefevre syndrome with malignant melanoma had not been elucidated yet. A 46-year-old woman presented with 7.0 X 6.0 cm sized ulcerative pigmented patch on her left sole which was growing slowly for 2 years. Palmoplantar keratoderma and premature loss of teeth had been observed since infancy and 13 years old, respectively, thus she was diagnosed with Papillon-Lefevre syndrome 16 years ago. A biopsy was performed on pigmented patch, and histopathologic examination showed masses of spindle-shaped cells, with nuclear polymorphism, and numerous mitotic figures. A diagnosis of acral lentiginous melanoma was established with consideration for clinicopathologic features and the patient was transferred to the plastic surgery department for wide excision. To our knowledge, this is the third report of a patient with Papillon-Lefevre syndrome in whom acral lentiginous melanoma developed in the literature. Because malignant melanoma is the cutaneous neoplasia with the greatest mortality rates, dermatologists should examine acral lesions carefully in Papillon-Lefevre syndrome patients.