Objective We are reporting a case of adipsic diabetes insipidus (ADI) post astrocytoma resection. Method Clinical and laboratory data are presented Results 16-year-old female with a history of incompletely resected hypothalamic astrocytoma admitted with headache. Head MRI showed interval increase in suprasellar lesion with extension to the third ventricle. Following second stage resection, she developed increased urine output with diluted urine resulting in negative fluid balance, however, she was unable to sense thirst. Blood tests showed serum sodium of 155 mEq/dl (136–145), serum osmolality at 321 mOs/kg ( 285–295 ) and urine osmolality of 128 mOsm/kg (300–1600 ). Serum creatinine and potassium were normal. Pituitary hormone profile were normal : Growth Hormone 0.171 ng/ml (0.123–8.05), LH 3.44 miu/ml (7.59–89.08), FSH 5.60 miu/ml (2.55–16.69) TSH 2.9 miu/ml (0.35–4.94), Free Thyroxine 0.92 ng/dl (0.7–1.48), ACTH 19.56 pg/ml (7.2–63.3) and Prolactin 7.25 ng/ml (5.18–26.53). The patient was treated with Desmopressin Acetate 120 mcg tablets twice daily with a fixed fluid intake of 1.5 to 2.0 liters/day with closed monitoring of fluid intake, output and body weight. Response was good with gradual reduction of serum sodium level of around 7–9 mEq/L/Day. Conclusions Adipsic diabetes insipidus is a rare entity of central diabetes insipidus, where the absence of polydipsia can be challenging in diagnosing and managing the condition. Cases of ADI are likely under reported and clinicians need to be aware of this condition