The pathogenesis of rheumatoid arthritis(RA) remains to be completely elucidated so far; however, it is known that proinflammatory cytokines play a pivotal role in the induction of RA. Tumor necrosis factor(TNF-α), in particular, is considered to play a central role in bone destruction by mediating the abnormal activation of osteoclasts or the production of proteolytic enzymes through direct or indirect mechanisms. The use of TNF-α blocking agents has a significant impact on RA therapy. Anti-TNF-α blocking agents such as infliximab are very effective for treatment of RA, especially for the prevention of articular destruction. We have previously shown that several proteins exhibited extensive changes in their expression after amelioration of RA with infliximab treatment. Among the proteins, connective tissue growth factor(CTGF) has a significantrole for the development of RA. Herein, we review the function of CTGF in the pathogenesis of RA and discuss the possibility of a novel treatment for RA. We propose that CTGF is a potentially novel effector molecule in the pathogenesis of RA. Blocking the CTGF pathways by biological agents may have great beneficial effect in patients with RA. The pathogenesis of rheumatoid arthritis (RA) remains to be completely elucidated so far; however, it is known that that proinflammatory cytokines play a pivotal role in the induction of RA. Tumor necrosis factor (TNF-α), in particular, is considered to play a central role in bone destruction by mediating the abnormal activation of osteoclasts or the production of proteolytic enzymes through direct or indirect mechanisms. The use of TNF-α blocking agents has a significant impact on RA therapy. We have previously shown that several proteins may produce extensive changes in their expression after amelioration of RA with infliximab treatment. Among the proteins, connective tissue growth factor (CTGF) has a significantrole for the development of RA. Herein, we review the function of CTGF in the pathogenesis of RA and discuss the possibility of a novel treat ment for RA. We propose that CTGF is a potentially novel effector molecule in the pathogenesis of RA. Blocking the CTGF pathways by biological agents may have great beneficial effect in patients with RA.