This study aimed to examine the effects of Thymosin Alpha 1 (Tα1) on the degree of arthritis and bone remodeling in animal models. The chronic autoimmune illness known as rheumatoid arthritis (RA) is marked by inflammation and joint damage, frequently with changes in bone metabolism. Tα1, an immune-modulatory peptide found naturally in the body, has demonstrated potential in reducing inflammatory reactions and accelerating tissue healing. The effects of Tα1 on arthritis progression and related bone alterations were evaluated in this study using a collagen-induced arthritis (CIA) model in wistar rats. Following treatment with Tα1 at three different doses (0.25 mg/kg, 0.5 mg/kg, and 1 mg/kg), the animals were observed for signs and symptoms of arthritis, joint swelling. As indicated by a decrease in joint inflammation, our findings show that Tα1 therapy reduced the severity of arthritis. In arthritic joints, Tα1 therapy increased anti-inflammatory responses and inhibited the production of pro-inflammatory cytokines. Moreover, the injection of Tα1 resulted in an increase in osteoblast activity and a decrease in osteoclast-mediated bone resorption, hence enhancing bone quality and integrity. Tα1 may be a useful therapeutic agent for reducing the severity of arthritis and maintaining