An empty sella may develop as a consequence of a primary congenital weakness of the diaphragm for which no secondary cause is evident. A secondary empty sella may develop after infarction of a pituitary adenoma or because of surgical or radiation-induced damage to the sellar diaphragm. Acromegaly is caused by growth hormone (GH) hypersecretion and the resultant elevated levels of circulating insulin like growth factor-1. The underlying abnormality in more than 98% of cases is hypersecretion of GH by a pituitary GH-producing tumor. Necrosis and hemorrhage, which frequently occur in pituitary adenomas, may lead to complete or partial disappearance of the adenoma, and subsequently, to an empty sella. We report two cases of acromegaly with empty sella, and the patients had no symptoms of pituitary apoplexy.