Thoracoscopic parathyroidectomy (TP) is a preferred approach to the treatment of hyperparathyroidism (HPT), caused by hyperfunctioning parathyroid glands located in mediastinum, though the data on its feasibility and safety are scarce, due to the rarity of this condition. Objective — to assess the safety and feasibility of thoracoscopic parathyroidectomy. Materials and methods. A retrospective cohort included 25 patients (14 male, 11 female) of primary thoracoscopic parathyroidectomy performed in Kliniken Essen‑Mitte and Wuppertal Helios Hospital from August 2002 to December 2024. Out of the patients included in the study, 15 patients underwent TP as their initial operation for primary HPT (pHPT), 7 patients had persistent pHPT after cervical operations, one — recurrent pHPT, and two — recurrent secondary HPT. Median age was 60 years (range: 27—77 years). The mediastinal location of the parathyroid was suspected by (99m)Tc‑sestamibi (MIBI)‑scintigraphy in 18 cases, five cases were MIBI‑negative, and in two cases, no MIBI‑scintigraphy was performed. In all cases, parathyroid localization was confirmed by 4D Computed tomography (CT) scan (n=17), magnetic resonance imaging (MRI) (n=3) or Positron emission tomography (PET‑CT) (n=5). Pre‑ and postoperative levels of serum calcium and parathormone, histopathological reports, and surgery protocols were analyzed. Intraoperative parathyroid hormone (PTH) level was measured with a rapid assay to confirm the success of the procedure 15 minutes after resection. Results. During the investigated period, 26 thoracoscopic operations were performed. Overall success rate was 84.6% as in 4 cases no hyperfunctioning parathyroid tissue was thoracoscopically removed. In the first case, a cervical approach was required; in the second one, the patient was reoperated thoracoscopically one year later; in the third case, the operation resulted in the normalization of serum calcium level despite the absence of parathyroid tissue in the pathological specimen. In one more case, the patient demonstrated postoperatively elevated PTH level with normal serum calcium level. Median duration of operations was 80 minutes (range: 20—320 minutes). No perioperative deaths or major complications occurred. No conversion to sternotomy or thoracotomy was performed. A complication rate was 4.2%, including one case of chylothorax, followed by a successful retroperitoneoscopic ligation of the thoracic lymphatic duct, and one case of temporary phrenic palsy. Median postoperative hospital stay was 2 days (range 2—6 days). No readmissions due to any reasons after discharge were registered. Conclusions. Thoracoscopic parathyroidectomy is safe and feasible, being the optimal treatment option in most cases of mediastinal parathyroid adenomas. However, it requires precise preoperative localization to guarantee the success of the treatment.