Struma ovarii is a rare ovarian tumour, first described in 1889 by Boettlin. It defined the presence of thyroid tissue comprising >50% overall mass. comprises 1% all tumours and 2-5% teratomas. Preoperative diagnosis struma difficult because symptoms, clinical presentation ultrasound are often similar to that carcinoma. Hence most patients diagnosed post operatively. Most cases strum aovarii...