Most clinically non-functioning pituitary tumour arise from gonadotroph cells. However, clinically functional pituitary gonadotroph adenoma is rare. Here we report a female case who presented with menstrual disturbances, however further workup demonstrated a pituitary microadenoma with elevated FSH and oestradiol level. Transsphenoidal resection was performed and the surgical histopathology confirmed pituitary gonadotroph adenoma. Postoperatively, improvement in both symptoms and hormonal profile were observed. Interestingly, the initially enlarged and polycystic ovaries became within normal range around eight months after the surgery. We suggest functional gonadotroph adenoma should be considered in the presence of gynaecological disorder with persistently elevated oestradiol and FSH levels.