Background: The surgical treatment of primary hyperparathyroidism (HPT) in patients with multiple endocrine neoplasia type 1 (MEN1) has evolved due the concern of permanent hypoparathyroidism. As the diagnosis has increased, the extent of operation has decreased. Most MEN1 patients requiring parathyroidectomy are younger than 50 years and they pose a difficult balance to achieve between persistent HPT and life-long hypoparathyroidism. The aim of the present study is to review our experience with a large series of patients with MEN1-related HPT (HPT/MEN1) treated at a single institution in order to find clues to a better treatment decision in these younger cases. Method: Retrospective analysis of consecutive HPT/MEN1 cases treated at a single institution with different operations: total parathyroidectomy and immediate forearm autograft (TPTX-AG), subtotal (STPTX), unintentional less than subtotal (U-LSTPTX) and intentional less than subtotal parathyroidectomy (I-LSTPTX). Results: Considering 84 initial cases operated on since 2011 (TPTX-AG, 39; STPTX, 22, U-LSTPTX, 13, and I-LSTPTX, 10), the rates of hypoparathyroidism were 30.8% (U-LSTPTX), 28.2% (TPTX-AG), 13.6% (STPTX), and 0% (I-LSTPTX). Two-thirds of them (68%; 57/84) were young (<50 years) or asdolescents. MIBI scan was more sensitive to show parathyroid glands and bilateral disease. Considering the concordance of MIBI and ultrasound for the possibility of unilateral clearance, it would be suitable to 22.6% of the cases. Intra-operative parathormone showed a significant decay even after unilateral exploration, but longer follow up is necessary. Overall, there were seven (4%) adolescents in 161 cases treated from 1987 to 2018, three underwent TPTX-AG and four had U-LSTPTX. Five are euparathyroid, one had mild recurrence, and one required a reoperation after 8 years due to the residual gland. Conclusions: Young patients are the most frequent candidates to parathyroidectomy. Less extensive procedures may be planned only if carefully reviewed preoperative imaging studies suggest a localized disease. Patients and their relatives should be fully informed of the risks and benefits during consent process. Future research with larger cohorts and long-term results are necessary to clarify if less than I-LSPTX or unilateral clearance are really adequate in selected groups of patients with HPT/MEN1 presenting lower volume of disease detected by preoperative imaging studies.