Objective To analyze the expression of miR-4524a-3p in peripheral blood mononuclear cells （PBMCs） and major immune cell subsets of patients with systemic lupus erythematosus （SLE）， and evaluate its clinical application. Methods Peripheral blood samples were collected from SLE patients and healthy controls， followed by isolation of PBMCs， CD3⁺ T lymphocytes， CD19⁺ B lymphocytes， and CD14⁺ monocytes using human peripheral blood lymphocyte isolation solution （Ficoll） and immunomagnetic bead cell sorting. The expression level of miR-4524a-3p was quantified using fluorescence quantitative PCR. Pearson's linear correlation analysis was performed to assess the relationship between miR-4524a-3p expression and the disease activity score in SLE patients （SLEDAI）. Additionally， the diagnostic efficacy of miR-4524a-3p for SLE was evaluated by constructing a receiver operating characteristic curve （ROC）. Results The expression of miR-4524a-3p was significantly decreased in PBMCs （P < 0.05）， CD3⁺T cells （P < 0.001）， and CD14⁺ monocytes （P < 0.001） from patients with SLE compared to healthy controls. Furthermore， it exhibited a negative correlation with SLEDAI score （r = -0.406，P < 0.01）. Notably， the expression level of miR-4524a-3p was significantly lower in patients with moderate or severe active stage than those in mild and inactive stages （P < 0.01）. In addition， the SLE subgroup with lupus nephritis and joint involvement displayed lower levels of miR-4524a-3p compared to the subgroup without such manifestations （P < 0.01）. Importantly， ROC analysis demonstrated that miR-4524a-3p holds promising diagnostic value for SLE. Conclusion The expression of miR-4524a-3p was significantly diminished in CD3⁺ T cells and CD14⁺ monocytes derived from patients with SLE， exhibiting a close association with disease activity and demonstrating potential clinical diagnostic value for SLE.