Introduction: Malignant struma ovarii is an extremely rare ovarian tumour containing malignant thyroid carcinoma within differentiated thyroid tissue, as the predominant tissue type. Surgery for suspected ovarian tumour and incidental pathological diagnosis is the most common presentation. Evidence supporting any particular approach to the clinical management of this condition is limited, mainly consisting of case reports, small series or pathological case series. There is no randomised evidence for postoperative management in view of the rarity of this condition. The opinion is divided between conservative management versus total thyroidectomy and radio‐iodine ablation. Methods: We carried out a retrospective review of our series with focus on postoperative management of this rare condition. A review of existing literature was also carried out. Results: Six patients with a median age of 52 years presented with various symptoms of abdominal pain, pressure or menstrual problems. After the initial gynaecological resection and specialised pathology review, they were subsequently treated with total thyroidectomy and administration of radioactive iodine. All of these six patients are in remission at a median follow up of 60 months. Conclusion: We favour aggressive postoperative management with total thyroidectomy and radioactive iodine, and long‐term follow up of these patients.