Neuronal ceroid lipofuscinoses (NCLs) represent a large group of inherited neurodegenerative disorders characterized by an abnormal accumulation of lipopigment in neuronal and extraneuronal cells. The authors present a case of juvenile neuronal ceroid lipofuscinosis in a 7-year-old boy. Ultrastructural examination of a skin biopsy disclosed deposits of curvilinear profiles and fingerprint-like structures in epithelial cells of sweat glands, endothelial cells, peripheral nerve endings, and fibroblasts. These findings allowed specific confirmation of the assumed diagnosis of juvenile neuronal ceroid lipofuscinosis. Due to the genotypic and phenotypic variability within the group of NCLs, the clinical investigation may be long and complicated. With the NCL disorders in mind, an accurate diagnosis based on ultrastructural examination of a skin biopsy may shorten this investigation, thus benefitting the patient.