Globulin should be <10ng/ml after thyroid cancer surgery, and the sensitivity of this index is not as good as that of those whose thyroid tissue is not completely removed by treatment. Thyroid gland is the only source of thyroglobulin, if thyroid tissue is completely cleared after surgery and 131 radionuclide treatment, there should be no globulin in the blood, if the globulin is <1ng/ml, the efficacy of the treatment is satisfactory, and the frequency of follow-up can be reduced, the globulin is <10ng/ml, and continuous follow-up is needed, and those with ≥10ng/ml should be examined immediately to see if there is recurrence or incomplete clearance of thyroid cancer. Tissue residue is not completely removed. If the thyroid gland is not completely removed during surgery (unilateral lobectomy or lobectomy with isthmus), the residual thyroid tissue will still secrete globulin, and the significance and sensitivity of globulin detection for postoperative monitoring is not as good as that for those who have been completely cleared. Globulin ≥10ng/ml is generally considered to have some predictive value for recurrence, so thyroglobulin <10ng/ml is also required. Thyroglobulin is generally required to be rechecked every 3-6 months after surgery in patients with thyroid cancer, and it is recommended that patients follow their doctor's instructions for follow-up checkups.