The natural course and optimal treatment for isolated hypothalamic Langerhans cell histiocytosis (LCH) are unknown. We describe an adult female in whom total resection of a hypothalamic LCH granuloma was performed 12 years after transphenoidal resection of a pituitary adenoma. A retrospective review of the histological specimen of the first operation revealed CD1a positive cells characteristic of LCH along with a plurihormonal adenoma 12 years earlier. No other manifestations of LCH were found and MRI of the brain at the last follow-up 4 years after surgery did not show any recurrent or additional lesion. The diagnosis of isolated hypothalamic LCH is only possible by biopsy and our case demonstrates the feasability of a gross total resection in certain cases.