• Age:5-25 years old(including threshold);

• Diagnosed with AAV according to the 2022EULAR/ACR AAV classification criteria；despite of the Treatment with glucocorticoids (more than 1mg/kg/ day), cyclophosphamide, and rituximab for at least 3 months, still cannot achieve sustained response or disease recurred after response; Or use glucocorticoid combined with cyclophosphamide/rituximab plus more than one of the other immunosuppressants (including azathioprine, moxophenolate, methotrexate, leflunomide, tacrolimus, cyclosporine, beliuzumab, etc.) ≥3months，still failed to achieve sustained remission or relapsed after remission; Or meet the diagnostic criteria for severe vasculitis, clinical routine treatment is ineffective, the benefit is judged by the investigator to outweigh the risk, and the patient or guardian has fully informed consent, can be considered for inclusion。

• patient \<18 years old：PVAS≥15（total 63）；≥18 years old: BVAS≥15(total 63)

• The functions of important organs are basically normal: Cardiac function: Left ventricular ejection fraction (LVEF) ≥55% with no obvious abnormality in electrocardiogram; Renal function: eGFR≥30ML/min/1.73m2； Liver function: Asparagus cochinchinensis transase (AST) and Alanine Aminotransferase (ALT)≤3.0 ULN, Total Bilirubin (TBIL) in serum ≤2.0×ULN; Lung function: No serious lung lesions, SpO2≥92%;

• Met the standards of leukapheresis or intravenous blood collection, No contraindication for cell collection;

• Negative pregnancy test for female Subjects of childbearing age, agree to take effective contraceptive measures the first year after CAR-T infusion;

• Participants or their guardians agrees to participate in the clinical trial and sign the informed consent form which indicating that he/she understands the purpose and procedure of the clinical trial and is willing to participate in the study.