PURPOSE: This single-center retrospective study explores the safety and efficacy of Lu-DOTATATE in children and young adult population with metastatic/inoperable neuroendocrine tumors (NETs). PATIENTS AND METHODS: This study is a retrospective analysis of all children and young adult patients (≤29 years) with advanced inoperable/metastatic epithelial or nonepithelial NETs who were administered a median of 4 cycles of Lu-DOTATATE therapy and low-dose oral capecitabine as a radiosensitizer every 8–12 weeks, except 2 patients who received CAPTEM chemotherapy. The radiological response was assessed using RECIST 1.1 on interim and end-of-treatment Ga-DOTANOC PET/CT. The primary endpoint was objective response rate, whereas disease control rate, toxicity profile, progression-free survival, and overall survival were secondary endpoints. RESULTS: Nineteen biopsy-proven NET patients (median age, 22 ± 10 years) with 8 of them adolescents (10–18 years) and the remaining young adults (19–29 years) were included. Fourteen patients had gastroenteropancreatic neuroendocrine tumor (pancreas being most common primary site), whereas the rest had non–gastroenteropancreatic neuroendocrine tumor. A total of 65 cycles of Lu-DOTATATE (range, 1–6 cycles) were administered with a median cumulative activity of 600 mCi (range, 100–1000 mCi). The objective response rate and disease control rate were 41% and 94%, respectively. Grade 1 and 2 adverse events were observed in 14 (74%) and 5 (26%) of 19 patients, respectively. In a total of 8 events (42%), 4 events each of disease progression and death occurred during a median follow-up of 80.1 months with an estimated 5-year progression-free survival and overall survival of 54% (95% confidence interval, 30–78) and 63% (95% confidence interval, 39–87), respectively. CONCLUSIONS: Lu-DOTATATE appears safe and effective in children and young adults with metastatic/inoperable NETs. Large prospective trials are required to validate these results.