Sebaceous carcinoma arising from ovarian mature cystic teratomas (MCTs) is exceedingly rare, with only 19 cases reported in the literature. We present a novel case of a woman in her 60s who experienced lower abdominal pain and a large pelvic mass. She underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, lymph node dissection, omentectomy and peritoneal washings. Intraoperative frozen section analysis confirmed a malignant tumour, favouring squamous cell carcinoma, possibly arising from an MCT. Postoperative recovery was uneventful, and she remains disease free after 28 months.Our review revealed that most cases presented at early International Federation of Gynecology and Obstetrics (FIGO) stages (70%), with unilateral tumours averaging 16.7 cm. Surgery was the mainstay of treatment, with salpingo-oophorectomy performed universally. Adjuvant chemotherapy was infrequent (20%), and mismatch repair deficiency was noted in 57.1% of tested cases. The median disease-free interval was 19 months. This case underscores the rarity of sebaceous carcinoma in MCTs and highlights the critical need for further research to establish evidence-based guidelines for optimal management and prognosis.