Familial adenomatous polyposis (FAP) is an autosomal dominant condition characterized by multiple colorectal adenomas that can progress to carcinoma. FAP can be associated with diverse extracolonic manifestation, including desmoid tumors and adrenal masses. We report our experience with a patient diagnosed of FAP, who developed a desmoid tumor and an adrenal mass in the follow-up. To our knowledge, this is the first case in the literature in which a hypersecretion of aldosterone and cortisol in the adrenal mass of a patient diagnosed of FAP has been demonstrated.