This investigation leverages data derived from the United States Food and Drug Administration Adverse Event Reporting (FAERS) to real-world adverse reactions associated with Belimumab, with the intention of providing guidance for safe clinical pharmacotherapy. Data encompassing adverse drug event (ADE) reports relating to Belimumab from Q1 2011 to Q4 2023 within the FAERS were extracted and analyzed using methodologies such as the reporting odds ratio (ROR), proportional reporting ratio (PRR), Bayesian Confidence Propagation Neural Network (BCPNN), and Multi-item Gamma Poisson Shrinker (MGPS). The study identified a total of 19 825 ADE reports where Belimumab was the primary suspect medication, with the United States constituting the majority of reporting countries (16 312 cases, or 82.28%). Patients aged 18 to 64.9 years accounted for the largest demographic (36.29%), while the proportion of female patients (77.91%) significantly surpassed that of male patients (5.03%). The analysis uncovered 184 unique Preferred Terms (PTs) across 21 System Organ Classes (SOCs). Following selection through ROR, the SOC signal strength was prioritized as follows: Systemic disorders and administration site conditions, infections and infestations, a variety of musculoskeletal and connective tissue disorders, and conditions related to pregnancy, puerperium, and the perinatal period. The top five PTs for ADE reports not included in the product's labeling were hypersensitivity reactions, immunosuppression, non-vascular diseases, herpes virus infections, and Sjögren's syndrome. The top five PTs for ADE signal strength not included in the labeling were disseminated cutaneous herpes zoster, herpes zoster meningitis, onycholysis, cyclothymic disorder, and mixed connective tissue disease. Based on pharmacovigilance research utilizing the FAERS database, it is recommended that clinical monitoring of Bevacizumab should be intensified to support effective pharmaceutical care and ensure rational clinical medication use.