Abstract Background Systemic lupus erythematosus (SLE) is an autoimmune disease caused by the disorders of immune regulation. In the past few years, increasing evidence has shown that progranulin (PGRN) is an immunomodulatory protein that is upregulated in SLE patients. Progranulinmay be involved in the pathogenesis of SLE, so, it might be a marker for disease activity. Objectives This work aimed to investigate the clinical significance of PGRN in patients with SLE regarding its role in pathogenesis and its relation to clinical manifestations and disease activity. Subjects and Methods This case-control study was conducted on 50 SLE patients classified according to the 2019 European League Against Rheumatism and the American College of Rheumatology (2019 EULAR/ACR), and were subdivided according to SLE Disease Activity Index-2000 (SLEDAI-2K) score into 25 patients with low disease activity (LDA) and 25 with high disease activity (HDA), in addition to 20 patients with autoimmune diseases other than SLE, and 20 healthy adults as a control group. We measured concentrations of serum PGRN with quantitative enzyme-linked immunosorbent assay (ELISA) in all studied participants. We assessed the correlation between the serum PGRN levels and different laboratory parameters, clinical symptoms and established disease-activity indices. Results Serum PGRN levels were significantly higher in SLE patients than healthy controls as well as when compared to the group of patients with autoimmune diseases other than SLE. They also significantly correlated with values of laboratory assays and clinical parameters such as ESR, 24 hours urine protein, SLEDAI-2kscore, and total damage scores; and inversely correlated with C3, C4 and Hb concentrations. Conclusion Serum PGRN could be a useful biomarker for disease activity of SLE.