Systemic lupus erythematosus (SLE) is an autoimmune disease. Cytokine-mediated immunity plays an important role in the pathogenesis of SLE. TNF-like ligand 1A (TL1A) belongs to the TNF superfamily of cytokines and has been found to perform significantly in autoimmune diseases, such as rheumatoid arthritis and inflammatory bowel disease. To date, no study has discussed the expression levels of TL1A in SLE. We found that plasma levels of TL1A were significantly higher in newly diagnosed SLE patients compared with controls. Correlation analysis showed that plasma levels of TL1A were positively associated with SLE disease activity index. These data indicated that TL1A may play a role in SLE and may reflect the disease activity for SLE.