Erdheim-Chester disease (ECD) is an uncommon non-Langerhans cell histiocytosis that affects multiple body systems and can present clinically in a myriad of ways. An adult onset is most common with bony involvement and constitutional symptoms. We report the case of a 52-year-old female presenting with diabetes insipidus and a suprasellar mass on imaging, with no evidence of extracerebral involvement. Histopathology was consistent with ECD.