Background: Struma  ovarii  is a specialized  monodermal  teratoma, constituting 1-4% of benign ovarian teratoma. Composed  predominantly  of mature thyroid tissue of more than 50%.Based on histological features it can be classified into benign and malignant.The overall incidence of dermoid cyst is 20-25%. Case: A 28 year old multipara (G3P2L2) reported to VIMS labour  room complex in active phase of labour at term gestation with hand prolapse with previous history of full term normal deliveries. Conclusion: Struma  ovarii  is a rare  tumor of ovary. Diagnosis  is made by histopathological findings.The optimal treatment for benign  tumor   is surgical resection  i.e. either simple cystectomy or unilateral oophorectomy.Malignant cases need adjuvant treatment. Recurrence is uncommon.