The purposes of this study are to evaluate the merits of surgical treatment, including subtotal parathyroidectomy (SP) and total parathyroidectomy (TP), in patients with tertiary hyperparathyroidism (THPT) and compare the outcome of the two surgical options. Medical records of patients undergoing parathyroidectomy for THPT were retrospectively reviewed and long-term outcomes between the two groups were compared. Fourteen out of 488 renal transplantation recipients required parathyroidectomy for THPT during a 24-year follow-up period with a median follow-up of 35.5 [interquartile range (IQR), 19.3-133.3] months. All patients had hypercalcemia, whereas 13 had varying symptoms and one was asymptomatic. Median serum calcium level decreased from 12.4 (IQR, 11.9-12.6) mg/dL preoperatively to 8.9 (IQR, 8.1-9.4) mg/dL postoperatively (P = 0.001), whereas median intact parathyroid hormone (iPTH) dropped from a preoperative level of 340.5 (IQR, 247-540) pg/mL to 55.1 (IQR, 24.4-66.4) pg/mL after surgery (P = 0.018). Comparison between patients receiving TP and SP revealed no difference in incidence of recurrence or permanent complications, whereas the former had significantly lower calcium levels (P = 0.048) and higher phosphorus levels (P = 0.017) compared with the latter. Moreover, a significant reduction in calcium level was noted in TP group on long-term follow-up compared with their immediately postoperative level (8.1 vs 9.0 mg/dL, respectively, P < 0.05), whereas there was no significant decrease in SP group. We concluded that parathyroidectomy is efficient and safe in treating THPT. Because TP would increase the risk of hypocalcemia, a less radical procedure (SP) is preferred.