Objective: To explore the blood supplement regularity of large and huge pituitary adenomas. Mechods: Sixteen large and huge pituitary adenomas were removed by microsurgery via transorbitofrontosphenoidal approach. The blood vessels of the tumors coming from surrounding structures were observed, photographed, videotaped and measured during operation. Results: The blood supplement of the pituitary adenoma comes from not only the superior and inferior hypophyseal arteries, but also a lot of new arteries origin...