Acromegaly is a chronic disease leading to a multisystem and metabolic disease characterized by growth hormone (GH) hypersecretion resulting from adenoma of hypophysis. Acromegaly patients usually have insulin resistance and elevated plasma glucose levels due to increased GH action. But in the literature, diabetic ketoacidosis as a complication of acromegaly is rarely reported. The presented case report about a patient who had acromegaly and diabetic ketoacidosis emphasizes the importance of evaluating every single patient with secondary hyperglycemia resulting from other metabolic diseases.