We present a child with Lenz dysplasia associated with panhypopituitarism. Lenz dysplasia is characterized by small eyeball, small head, hydronephrosis, cleft lip and palate, and mental retardation. A 12 month-old boy with Lenz dysplasia was scheduled for plasty of the lip and basis of the nasal cavity under general anesthesia. We had to pay attention for airway management and hormone supplementation. Anesthesia was induced with sevoflurane and nitrous oxide in oxygen. Tracheal intubation was facilitated with vecuronium bromide. We had no difficulty in airway management. Since this patient could not release enough endogenous cortisol in response to the stress of surgery, we supplemented hydrocortisone after anesthesia induction. Urine output and serum electrolyte concentrations were carefully monitored during surgery because of the impaired ADH response. We encountered no complications in the anesthetic management of this patient.