CA724 is a class of tumor markers frequently done in clinical practice, which can be used for screening of gastrointestinal tract tumors as well as ovarian cancer. Its positive rate in malignant tumors is the highest in gastric cancer, which can reach 69.7%. The normal value of CA724 is less than 6 U/mL, and if it is slightly elevated, say within 10 U/mL, it can be reviewed periodically at half a month to one month. We can see the dynamic changes. The elevation of CA724 alone is not sufficient to diagnose malignancy. If CA724 is significantly higher than the normal value, it should be combined with the patient’s clinical manifestations and the improvement of CT and ultrasound imaging. If CA724 is significantly higher than normal, it should be combined with the patient’s clinical manifestations and the improvement of CT and ultrasound imaging to confirm whether the patient has malignant tumor.