Collagen triple helix repeat containing-1 (CTHRC1), is a 28-kD extracellular matrix glycoprotein. CTHRC1 is expressed mostly in adventitial fibroblasts and increases cell motility by limiting the deposition of collagen matrix and promoting cell migration. CTHRC1 is produced by activated fibroblast-like synoviocytes (FLS) and primarily promoted FLS polarization and increased the migration speed and directness of cell movement which resulted in production of arthritic pannus. RA has great variation in clinical presentation, the presence of specific serological markers and the extent of joint involvement and bone erosion. SLE is heterogeneous in presentation characterized by many pathogenic autoantibodies and uncontrolled inflammatory response leading to organ damage.So it is of importance to search for markers for better evaluation and monitoring of both diseases