Lymphocytic hypophysitis is an unusual inflammatory lesion that is caused by autoimmune destruction of the pituitary gland. We report a case of 42-year-old man who presented with a 6-month history of severe headache, blurred vision in the right eye, hearing loss, polyuria, polydipsia, and impotence. Medical history showed that he and his mother had osteopetrosis. The results of the physical examination and laboratory tests showed that secondary hypothyroidism, hypogonadism, and hypocortisolism had developed. Central diabetes insipidus was diagnosed by water deprivation test. MRI of the sella showed pituitary enlargement with symmetrical suprasellar expansion, compression of the chiasma, thickened infundibulum, and involvement of both bilateral cavernous sinuses and clivus. Hormonal substitution with hydrocortisone, levothyroxine, and DDAVP resulted in rapid improvement of all symptoms and signs. Transsphenoidal biopsy was diagnostic of lymphocytic hypophysitis. In spite of extensive literature reviewing, we have not been aware of any case of lymphocytic hypophysitis with clivus involvement. The present case represents a variant of lymphocytic hypophysitis which has progressed to involve bilateral cavernous sinuses and the clivus.