The normal value of glycogen antigen 125 varies from hospital to hospital, but in most hospitals the normal value of glycogen antigen 125 is less than 35 U/mL. The main clinical value of glycogen antigen 125 is to indicate whether ovarian cancer or gastrointestinal tract tumor is present, especially for women with ovarian cancer. If it is greater than 35U/mL, it needs to be followed up dynamically with abdominal CT, ultrasound, etc. to rule out any occupying ovarian lesions. If CA125 (glycoantigen 125) is elevated, the ovarian mass should be removed or pathology should be performed to determine if it is an ovarian nevus. It is also important to note that elevated CA125 (glycoantigen 125) is related to the development of gastrointestinal tumors. If CA125 (glycoantigen 125) is elevated, abdominal CT or even gastroscopy or colonoscopy should be done to rule out gastrointestinal tumors.