Acromegaly is, in most cases, caused by growth hormone secreting pituitary adenomas. Those patients often develop different pathologies of the thyroid gland, however, the occurrence of Grave´s disease is quite a rare situation. We report a case of a 64-year-old female patient who presented with signs of hyperthyroidism and imbalance of her diabetes mellitus. On physical examination, she had facial features of acromegaly. Biochemical testing confirmed the suspicion of acromegaly and Grave´s disease, with an elevated insulin-like growth factor-1 and a suppressed thyroid stimulation hormone (TSH) with positive TSH-receptor antibodies. A pituitary Magnetic Resonance Imaging (MRI) was performed, revealing a macro-adenoma and an empty sella. The patient successfully underwent a transsphenoidal surgery and obtained a remission of her hyperthyroidism under anti-thyroid drugs.