To summarize the clinical characteristics, diagnosis and treatment of congenital renal diabetes insipidus (CNDI) in neonates. A case of CNDI in　Kunming Children's Hospital was retrospectively analyzed, and the clinical signs, routine examinations, diagnosis and treatment of CNDI were summarized. A 23-day-old boy was considered for CNDI because of prolonged infection, refractory to treatment, low specific gravity urine, and hypernatremia, and this diagnosis was confirmed by genetic testing. The symptoms of diabetes insipidus were relieved for a long time after treatment with hydrochlorothiazide, spironolactone and ibuprofen. Neonates with unexplained elevated plasma osmolarity and low specific gravity urine need to consider CNDI in time and improve the relevant examinations. The disease often requires combined medication to control symptoms. Hydrochlorothiazide and spironolactone combined with ibuprofen can be considered as a reference for infant treatment.