Takayasu's arteritis (TAK), a chronic large vessel vasculitis, involves the aorta and its main branches. Glucocorticoids and immunosuppressants such as methotrexate, cyclophosphamide are common agents for TAK treatment. However, their effects for remission induction and relapse prevention are not satisfied. More effective agents for TAK treatment remain to be investigated. Tofacitinib (TOF) is a Jak inhibitor, which has been proved to be effective in multiple autoimmune diseases such as rheumatoid arthritis. Our preliminary real-world study also demonstrated a promising treatment effect of TOF in patients with TAK. But its efficacy and safety needs further verification. The present randomized controlled trial aimes to compare efficacy between methotrexate and tofacitinib in TAK treatment.