Early diagnosis of refractory Mycoplasma pneumoniae pneumonia (RMPP) in children presents significant clinical challenges. Emerging evidence suggests that circ_0054633 may serve as a promising diagnostic biomarker for pulmonary infections. We developed a comprehensive nomogram integrating circ_0054633 expression with clinical features to evaluate its predictive efficacy for early RMPP diagnosis in children. This retrospective study analyzed 244 children with Mycoplasma pneumoniae pneumonia (MPP) admitted to Tianjin Children's Hospital during 2023. Multivariate analysis identified six independent predictors: elevated circ_0054633 (OR = 6.28, 95% CI: 2.73-14.47), prolonged fever duration (OR = 1.50, 95% CI: 1.24-1.81), hypoxemia (OR = 10.64, 95% CI: 2.75-41.20), extrapulmonary complications (OR = 2.95, 95% CI: 1.17-7.40), elevated IL-6 (OR = 1.02, 95% CI: 1.00-1.03), and atelectasis (OR = 3.16, 95% CI: 1.25-8.00). The nomogram demonstrated excellent discrimination (AUC = 0.920) and calibration. RMPP patients required longer hospitalization (median 9 vs. 7 days, P < 0.001) and more interventions. The circ_0054633-based nomogram, incorporating clinical predictors, exhibits strong predictive value for RMPP in children. Serum circ_0054633 shows promise as a novel diagnostic biomarker for RMPP.