Incontinentia pigmenti(IP), so called Bloch-Sulzberger syndrome is a rare hereditary neurocutaneous syndrome and was described first by Bardach in l925. This disorder is known as a systemic disease caused by a defect at the developmental stage of organs originated from ectoderm or mesoderm. Incontinentia pigmenti is presented by characteristic linear hyperpigmented skin lesions, often associated with central nervous system involvement, dysplasia in the dental system, and ocular abnormalities. This disorder occurs almost in female infants, usually lethal in males, inherited as X-linked dominantly. Thirty percent of the patients suffer from central nervous system complications such as mental retardation, encephalopathy, delayed development, seizure, spastic paralysis and microcephaly. We report a case of a 12 month-old female with incontinentia pigmenti who was hospitalized with linear hyperpigmented skin lesions and delayed development.