Systemic lupus erythematosus (SLE) is an idiopathic multi-systemic autoimmune disease that covers a wide array of clinical and laboratory findings. Neutrophil to lymphocyte ratio (NLR) is a simple onsite available recently emerged inflammatory marker which is evaluated in different inflammatory conditions such as infection, athero-embolic disease, malignancies and autoimmune disease. In this study we aimed to investigate any relation between disease activity and NLR of the SLE patients with renal involvement.