This report describes a case of diabetes insipidus associated with acute myelogenous leukemia. An 11-year-old boy presented with fatigue, polydipsia and polyuria. His evaluation revealed a diagnosis of acute myelogenous leukemia FAB-M2, and a water deprivation test confirmed the diagnosis of central diabetes insipidus. His brain magnetic resonance imaging (MRI) showed a thickened, enhancing pituitary stalk with absence of the normal hyperintense signal in the posterior pituitary. He was treated with systemic chemotherapy, intensive intrathecal therapy, and 1,000 cGy to the pituitary. The patient achieved a remission but continued to need desmopressin therapy to control his diabetes insipidus. Diabetes insipidus is a rare complication of acute myelogenous leukemia that can be caused by leukemic infiltration of the pituitary. The diabetes insipidus is irreversible despite intensive systemic and central nervous system chemotherapy and radiation.