The challenging aspect of this case was that the patient was a 19-year-old unmarried woman with bilateral mature cystic teratoma of the ovary. The whole of the left ovary was involved in the dermoid cyst without any normal ovarian tissue. An Ovarian dermoid cyst is a saclike growth that is present at birth. It contains structures such as hair, fluid, teeth, or skin glands that can be found on or in the skin. Dermoid cysts grow slowly and are not tender unless ruptured. They usually occur on the face, inside the skull, on the lower back, and in the ovaries. Superficial dermoid cysts on the face usually can be removed without complications. Removal of other, more rare dermoid cysts requires special laparoscopic techniques and training.