〔Abstract〕 Objective To investigate the effect of total or near-total thyroidectomy on thyroid function in patients with thyroid cancer. Methods A total of 80 patients with thyroid cancer admitted to Jiujiang First People's Hospital from August 2019 to August 2020 were selected as the study objects and divided into groups according to the surgical methods. Forty patients who underwent total thyroidectomy were selected as a control group and 40 patients who underwent near-total thyroidectomy were selected as an observation group. The clinical treatment efficiency, operation status, thyroid function index, complication rate and recurrence rate were compared between the two groups. Results There was no significant difference in the total effective between the two groups (P > 0.05). The intraoperative blood loss in the observation group was less than that in the control group, and the operation time and hospital stay were shorter than those in the control group, with statistical significance differences (P < 0.05). After operation, parathyroid hormone, thyroglobulin and blood calcium indexes in the observation group were higher than those in the control group, and the differences were statistically significant (P < 0.05). The complication rate of the observation group was lower than that of the control group, but the recurrence rate was higher than that of the control group, the differences were statistically significant (P < 0.05). Conclusion Both total and near-total thyroidectomy can achieve certain therapeutic effects in the clinical treatment of thyroid cancer. Compared with total resection, the treatment of injury and thyroid function are less affected by near-total resection, and the operation is relatively safe, with fewer postoperative complications, but the probability of long-term recurrence may be greater.