Objective To explore the effectiveness of endoscopic radical thyroidectomy （ERT） through the chest breast approach on early papillary thyroid cancer and its impact on patient stress indicators, thyroid function, and parathyroid function. Methods From January 2020 to January 2023, a total of 62 patients with early papillary thyroid cancer diagnosed and treated in the hospital were selected as study subjects. They were randomly divided into a control group and an observation group by random number table method, with 31 cases per group. The control group received routine surgical treatment, while the observation group received ERT treatment through the chest breast approach. The thyroid function, parathyroid function （thyroid stimulating hormone （TSH）, thyroid hormone （T₄）, triiodothyronine （T₃）, and parathyroid hormone （PTH））, and stress indicators （cortisol （Cor）, superoxide dismutase （SOD）, and norepinephrine （NE）） were compared between the two groups. Results After operation, the levels of T₃, T₄, PTH, and SOD in the observation group were higher than those in the control group （P>0.05）; the levels of Cor, NE, and TSH in the observation group were lower than those in the control group （P<0.05）. Conclusion The use of transthoracic breast approach ERT treatment for early papillary thyroid cancer can reduce stress response and maintain thyroid and parathyroid functions of patients.