Background: Although anti-double-stranded DNA (dsDNA) antibodies is diagnostic markers for systemic lupus erythematosus (SLE), their limitations necessitate the identification of supplementary biologically relevant biomarkers to enhance diagnostic accuracy. Objective: To evaluate serum levels of mitogen-activated protein kinase 4 (MAPK4) and extracellular signal-regulated kinase 5 (ERK5) in patients with active SLE and determine their individual and combined diagnostic performance relative to anti-dsDNA antibodies. Patients and methods: This study involved 119 women with active SLE and 61 healthy female controls. Serum concentrations of MAPK4, ERK5 and the anti-dsDNA index were quantified using enzyme-linked immunosorbent assays (ELISA). Diagnostic performance was analyzed using receiver operating characteristic (ROC) curves, principal component analysis (PCA), and multivariate logistic regression. Results: SLE patients showed a significant increase in MAPK4, ERK5 and anti-ds DNA levels compared with the controls (all P < 0.001). The ROC curves for all have AUCs of 0.99. PCA demonstrated that the three biomarkers loaded onto a single dominant component that explained most of the variance. A logistic model combining the three markers achieved classification accuracy of 99.4 %. The three biomarkers showed consistent behavior within the composite statistical model between them, suggesting that they are involved in a shared immunological pathway. Conclusion: Serum MAPK4 and ERK5 levels were significantly elevated in active SLE, demonstrating exceptional diagnostic performance comparable to that of anti-dsDNA antibodies. Integrating these novel kinases into a multi-marker serological panel substantially enhances the diagnostic capability for SLE, particularly when conventional markers yield inconclusive results.