The size of the left adnexal cyst that needs surgery depends on the patient’s condition. If it is a physiological cyst, surgery is generally not necessary; if it is a pathologic simple cyst with a mass size of more than 5 centimeters, surgery is generally recommended; if it is a pathologic mixed cyst, surgery should be carried out as soon as possible regardless of its size. 1. Physiological cysts: they are generally physiological cysts or corpus luteum cysts, etc. Most of the cysts will not continue to grow and will subside on their own, so there is no need for surgery for anechoic cysts that are 2 to 3 centimeters in size. 2. Pathological cysts: if the cysts are pathological simple cysts and the size of the cysts is more than 5 centimeters, surgery is generally recommended; if the cysts are pathological mixed cysts and the cysts are rapidly growing and have a tendency to malignant changes, surgery should be carried out as soon as possible regardless of the size of the cysts. It is recommended that women should have regular review after finding adnexal cysts, and once there is a tendency of malignant change, they should have surgery in time, and check the tumor markers before surgery to determine its benignity or malignancy, and follow up in time if they feel uncomfortable after surgery.