Hirsutism is a common clinical and psychological problem in women. Polycystic ovary syndrome and idiopathic hirsutism are the most common causes of hirsutism. Adrenal disorders are less common causes of hirsutism; the most common adrenal cause of hirsutism is non-classical congenital adrenal hyperplasia (NC-CAH). Hirsutism may be the presenting symptom of an adrenal carcinoma or adenoma. In this review, adrenal causes of hirsutism, the pathophysiology of the hirsutism in NC-CAH, and the treatment of hirsutism in these patients, are discussed.