Preoperative preparation for patients with ovarian teratoma includes various preoperative examinations, skin preparation and disinfection one day before surgery, eight hours of fasting and four hours of water fasting before surgery. Preoperative examination is an important work to ensure that the surgery can be carried out. Preoperative examination includes: blood and urine routine examination, liver and kidney function examination, coagulation four items, blood sugar, electrocardiogram, chest X-ray, tumor marker, hepatitis B, syphilis, AIDS, etc., and the examination is free of abnormality before tolerating the surgery. The day before the surgery, the patient should take a bath, the doctor should remove sweat hair and pubic hair from the surgery area and the surrounding area, the dirt in the umbilicus should be wiped off using turpentine or ether swabs, and an enema should be given the night before the surgery so that feces in the intestines can be discharged in time. Eight hours before the operation, fasting, four hours water fasting, empty the bladder.