Purpose: To determine the effect of parathyroid autotransplantation (PA) on postoperative hypocalcemia in cases of total thyroidectomy. Materials and Methods: Cases undergoing total thyroidectomy and PA were compared with age and sex-matched controls who had not undergone PA. The postoperative percentage changes (PC) of parathyroid hormone (PTH) and calcium (Ca+2) in the first 12-24 hours (12-24 -> hrpreop), between the 1st-3rd weeks (1-3 -> wkpreop) and at the 6th month (6mo -> preop), the rates of hypocalcemia (Ca+2< 8mg/dL) and low PTH level (PTH< 15 pg/mL), permanent hypocalcemia, inadvertent parathyroidectomy in both groups were compared. Results: The number of patients with PTH12-24hr<15 pg/mL was significantly higher (n:34,(55.7%)) than the number of patients in the control group (n:16(26.2%)), (p=0.001). The rate of decrease in the blood Ca+2 median PC (6mo -> preop) was significantly higher in the PA group (4.2%) than the control group (1.1%), (p=0.008). There was no significant difference between the 2 groups in terms of the postoperative frequency of hypocalcemia (p>0.05). In the PA & 50 group, the rate of inadvertent parathyroidectomy was higher than that of cases over age 50 (p=0.029). Conclusion: In spite of the presence of an increased postoperative hypocalcemia trend in cases requiring PA during total thyroidectomy, the rates of transient and permanent hypocalcemia were not different to the control cases. But the frequency of cases with low PTH level in cases undergoing PA was higher than that of the control cases. In cases of 50 years of age and under, who had undergone PA, the possibility of inadvertent parathyroidectomy increased.