Inclusion Criteria:  Ages 18-65, male or female Confirmed diagnosis of Ankylosing Spondylitis Syndrome of traditional Chinese medicine is blood stasis syndrome ASDAS-CRP (Ankylosing Spondylitis Disease Activity Score)≥2.1 Visual analogue scale (VAS) for night pain≥4分 Maintained stable doses of Sulfasalazine, Methotrexate, Leflunomide, etc. for more than 1 month if treating with Slow-Acting Antirheumatic Drugs Maintained stable doses of biologics for more than 3 month if treating with biologics Not use Nonsteroidal Antiinflammatory Drugs within 2 weeks Patients who have not participated in other clinical trials within 4 weeks Written informed consent  Exclusion Criteria:  Pregnant or breastfeeding or who expecting to conceive Psoriatic arthritis or Enteropathic arthritis AS with iritis or uveitis Abnormal liver function Abnormal kidney function，high level of Creatinine WBC (White Blood Cell)<3.0×10^9/L or with Hematological Disease Patients with poor control of hypertension or diabetes Acute or chronic infectious diseases Severe arrhythmia Patients with malignant tumors or with a history of malignant tumors Drug allergy Patients who had taken Yuxuebi tablet for more than 4 weeks with poor outcome Patients who are treating with Traditional Chinese medicine for promoting blood circulation and removing blood stasis Alcohol or drug abuse Participants who are not suitable for clinical trial under doctors' consideration.