Ovarian teratoma: originates from ovarian germ cells. It can occur at any age, with the majority being between 20 and 40 years old. It is the most common of ovarian tumors and about 95% are benign. Ovarian teratomas are mostly unilateral and will grow gradually. Common complications of ovarian teratoma: torsion, rupture, necrosis, manifested as severe lower abdominal pain; secondary infection and intracapsular hemorrhage can rapidly increase in size, obvious pressure pain, may be accompanied by fever; malignant rate of teratoma is about 2% to 4%. Treatment: The principle is early detection and early treatment. The best method for early detection of ovarian teratoma is ultrasonography. Once diagnosed, ovarian teratoma, regardless of its size, should be operated as early as possible. Minimally invasive laparoscopic surgery to remove ovarian teratoma has become the preferred surgical procedure for the treatment of ovarian teratoma and other adnexal tumors due to the advantages of less trauma, less interference, less pain, faster recovery and light postoperative adhesions. After ovarian teratoma resection, there is usually no impact on fertility and it is possible to have a normal pregnancy. The recurrence rate of ovarian teratoma is about 2%.