A case of unusual combination of polycystic ovaries (PCO), adrenal non-functioning adenoma and severe hirsutism in a young woman from Southern Italy is reported here. A 18-yr-old woman was referred to our Department because of oligomenhorrea, acne and severe hirsutism. During evaluation of the cause of her symptoms, PCO and small left adrenal adenoma were revealed. Although adrenal androgen excess has been shown to dysregulate the hypothalamic-pituitary-gonadal axis, causing PCO-like syndrome, normal circulating androgen values were found. Androgens and cortisol levels were completely suppressed by low-dose dexamethasone test, excluding autonomous steroid secretion by the adrenal mass. Normal response of cortisol and adrenal androgens to corticotropin stimulation test permitted the exclusion of functional adrenal hyperandrogenism. Despite normal LH/FSH ratio, anovulatory cycles were revealed by persistently low progesterone values. Glucose and insulin response to oral glucose tolerance test did not differ from those of normal population. The patient showed an improvement of acne and hirsutism on therapy with estro-progestins (EP). In conclusion, despite normal pattern of serum androgens and LH/FSH ratio, this patient had anovulatory cycles and good response to the EP treatment. These findings suggest that ultrasonography evidence of PCO together with anovulatory cycles contributed to her clinical picture whereas adrenal adenoma seemed to have no relevant role. This case report underlines the need of cautious interpretation of imaging results and clinical signs of severe hirsutism, reminding one that the true cause of a medical problem may not be the most evident.