Endothelial dysfunction (ED) has an important role in the pathogenesis of systemic lupus erythematosus (SLE). Studies on other inflammatory diseases show that salusin-β with various mechanisms may play a role in the promotion of ED and inflammation. The aim of this study was to measure serum salusin-β levels in SLE patients and evaluate it as a potential biomarker in assessing SLE activity and predicting organ involvement. In a cross-sectional study, 60 patients diagnosed with SLE and 30 age- and sex-matched healthy controls were enrolled. Disease activity of SLE patients was assessed by the systemic lupus erythematosus disease activity index 2000 (SLEDAI-2K). Serum levels of salusin-ß were measured using a human salusin-ß enzyme-linked immunosorbent assay kit. Serum salusin-β levels in SLE and control groups were 474.2 ± 117.1pg/ml and 157.7 ± 88.7pg/ml, respectively. The difference was significant (P = 0.001). There was no significant correlation between serum salusin-β levels with age (r = - 0.06, P = 0.632) and SLEDAI (r = - 0.185, P = 0.158). In patients with nephritis and thrombosis, serum salusin-β was significantly higher. In addition, in patients with serositis, serum salusin-β was significantly lower. Multiple linear regression analysis showed that serum salusin-β levels retained a significant association with nephritis and thrombosis after model adjustment for serositis, nephritis, and thrombosis. Our findings showed that salusin-β might have a possible role in the pathogenesis of SLE. Salusin-β may be a potential biomarker for nephritis and thrombosis in SLE. Key Points • Serum salusin-β levels were significantly higher in SLE patients than the control group. • There was no significant correlation between serum salusin-β levels with age and SLEDAI. • Serum salusin-β levels retained a significant association with nephritis and thrombosis.