We report here three patients with hypopituitarism accompanied by primary empty sella, whose first manifestations were various mental symptoms. Endocrine studies revealed that two patients showed panhypopituitarism and the other had isolated adrenocorticotropin (ACTH) deficiency. Although several different types of pituitary dysfunctions have been described in a mild form, empty sella is usually asymptomatic. Their first manifestations were mental symptoms; consciousness disturbance, psychomotor agitation, visual hallucination and delusion. Isolated ACTH deficiency is an uncommon disease which etiology is still undetermined. A case with isolated ACTH deficiency associated with an empty sella has been reported before. It is suggested that empty sella might have a role in pathogenesis of isolated ACTH deficiency. The empty sella was confirmed by metrizamide cisternography and magnetic resonance imaging (MRI). These imaging studies are good tools to disclose empty sella. Replacement with cortisone and levothyroxine resulted in an improvement in the mental symptoms in two patients with panhypopituitarism. No alteration was observed following cortisone administration in the patient with isolated ACTH deficiency. Delusion and visual hallucination in this patient poorly responded to treatment with neuroleptics.