Rheumatoid Arthritis (RA) is an autoimmune disease that results in a chronic inflammatory disorder that may affect many synovial joints, and may cause serious disability. It has been confirmed that Tripterygium Wilfordii has effects of anti-inflammatory, immunosuppressive and cartilage protection. This is a multicenter ,double Blind, randomized study to evaluated the efficacy and safety of Tripterygium Wilfordii in treating of patients with rheumatoid arthritis (RA) and establish a prediction model for Tripterygium Wilfordii response of rheumatoid arthritis (RA).

Two arms were included in this study. Active Comparator: treatment of MTX Patients were treated with methotrexate (MTX)and Tripterygium wilfordii Hook F（TwHF）placebo.Experimental: treatment of TwHF Patients were treated with methotrexate (MTX) and Tripterygium wilfordii Hook F（TwHF).

Inclusion Criteria:

• Diagnosed with rheumatoid arthritis as determined by the 1987 or 2010 ACR classification criteria;
• No male or female fertility requirements, or around menopause women;
• Patients with mild-to-moderate activity, 2.6 < DAS28≤5.1;
• No serious system involved, such as severe pericardial effusion, interstitial lung disease, renal tubular acidosis, atrophic gastritis, autoimmune liver disease, etc;
• Within a month before the selected participants did not attend any drugs

Exclusion Criteria:

• Patients with cancer or other malignant disease such as cardiovascular, hematopoietic, liver and kidney disease, and psychopath
• Active or chronic infection, including HIV, hepatitis C virus, hepatitis B virus, tuberculosis
• Previous treated with tripterygii, glucocorticoid or biologic disease-modifying antirheumatic drug (DMARD) in 3 months.
• Previous treated with Tripterygium Wilfordii or MTX
• Patients with retinopathy.