Objective: ¹⁷⁷ Lu-DOTA-TATE (LUTATHERA) is a crucial radiopharmaceutical in neuroendocrine tumor therapy, yet real-world long-term safety data across diverse populations remain limited. This study aims to comprehensively assess the postmarketing safety of LUTATHERA using a real-world pharmacovigilance database. Methods: We conducted an observational study using the US Food and Drug Administration’s Adverse Event Reporting System (FAERS) database from the first quarter of 2018 to the third quarter of 2024. Reports were filtered for LUTATHERA as the primary suspect. The characteristics and onset time of LUTATHERA-associated adverse events were analyzed. The disproportionality analysis via reporting odds ratio (ROR) and Bayesian confidence propagation neural network was employed to identify significant adverse event signals associated with LUTATHERA. Results: A total of 4058 reports identified with LUTATHERA as the primary suspected drug. LUTATHERA was linked to increased risks in in general disorders, gastrointestinal, hematological, metabolic, hepatobiliary, and endocrine systems. Common adverse events like nausea, thrombocytopenia, and anemia aligned with clinical trial data. Novel and serious signals such as intestinal obstruction [ROR = 5.62, information component (IC) = 2.49], gastrointestinal hemorrhage (ROR = 2.84, IC = 1.50), carcinoid heart disease (ROR = 571.03, IC = 8.93), and esophageal varices hemorrhage (ROR = 11.92, IC = 3.57) were also identified. LUTATHERA-associated adverse events typically occurred within 2 months, with a median onset of 54 days. Conclusion: This study enhances understanding of LUTATHERA’s safety profile, offers clinicians valuable data, and advocates continuous pharmacovigilance. Continuous pharmacovigilance and potential label updates are recommended.