Background <p>Neuroblastoma is a prevalent malignant tumor in children, with significant challenges in prognosis assessment. This study investigated the potential value of β2-microglobulin for predicting outcomes in patients with intermediate- to high-risk neuroblastoma.</p> Methods <p>We conducted a retrospective analysis of 40 patients with intermediate- to high-risk NB treated at the Children's Hospital of Kunming Medical University from 2018–2021. Peripheral blood and tissue samples were collected, and relevant biomarkers were detected via flow cytometry and real-time quantitative PCR (RT-qPCR).</p> Results <p>β2-microglobulin was the only biomarker significantly associated with NB prognosis. Patients in the high-expression group had a significantly greater three-year survival rate than those in the low-expression group (<i>P</i> &lt; 0.01). Logistic regression analysis, combined with clinical data and receiver operating characteristic curves, indicated that β2-microglobulin had predictive capabilities comparable to those of neuron-specific enolase, suggesting its potential role in treatment assessment and prognostic evaluation.</p> Conclusion <p>β2-microglobulin has significant prognostic value in intermediate- to high-risk neuroblastoma patients and may serve as an effective biomarker for clinical prognosis. These findings offer new insights for individualized neuroblastoma treatment, emphasizing the need for future research on its applicability in diverse populations and potential use in treatment monitoring.</p>