ACTH syndrome is mainly due to the pituitary gland or ectopic tumors, like lung tumors secrete a large amount of ACTH, which acts on the adrenal glands leading to adrenocortical hyperplasia and secretes a large amount of corticosteroid, leading to the patient’s typical clinical symptoms, such as a full-moon face, buffalo back, purple lines on the skin, high blood pressure, hypokalemia, and osteoporosis, etc. After the occurrence of the ACTH syndrome, it focuses on the two parts of the exclusion: i. The most common ACTH syndrome caused by pituitary ACTH tumors is the perfect pituitary enhancement nuclear magnetic examination. Second, ectopic ACTH syndrome, the more common is the lung tumor, digestive system carcinoid tumor can also lead to increased ACTH secretion.