Lymphocytic hypophysitis is an autoimmune disorder of the pituitary gland which usually occurs in a woman in the postpartum period. Diabetes insipidus is not a major clinical feature of this disorder. We report a case of a 22-year-old man with lymphocytic hypophysitis which presented with diabetes insipidus and also involved his cavernous sinus. This represents the seventh reported and the youngest case of a man with lymphocytic hypophysitis. A comparative study of all six male patients is also presented. We suggest diabetes insipidus should be added to the spectrum of clinical manifestations of this disorder.