The purpose of this study is to infusion BCMA CAR-T cells to the patients with relapsed and refractory multiple myeloma(MM), to assess the safety and feasibility of this strategy. The CAR enables the T cell to recognize and kill the MM cells through the recognition of BCMA, a protein expressed of the surface of the malignant plasma cells in MM patients.

Inclusion Criteria:

• 1. 18 years to 70 years, expected survival > 3 months;
• 2. Confirmed diagnosis of active MM as defined by IMWG. BCMA expression of the malignant cells must be detected by immunohistochemistry or by flow cytometry.
• 3. BCMA-expressing B cell malignancy must be assured and must be relapsed or refractory disease.；
• 4. ECOG performance status of 0-2;
• 5. Cardiac function: 1-2 levels; Liver: TBIL≤3ULN，AST ≤2.5ULN，ALT ≤2.5ULN; kidney: Cr≤1.25ULN;
• 6. No serious allergic constitution;
• 7. No other serous diseases that conflicts with the clinical program;
• 8. No other cancer history;
• 9. female participants of reproductive potential must have a negative serum pregnancy test;
• 10. Subjects must have signed written, informed consent.

Exclusion Criteria:

• 1. Pregnant or lactating women;
• 2. Uncontrolled active infection, HIV infection, syphilis serology reaction positive;
• 3. Active hepatitis B or hepatitis C infection;
• 4. Recent or current use of glucocorticoid or other immunosuppressor;
• 5. serious mental disorder;
• 6. With severe cardiac, liver, renal insufficiency, diabetes and other diseases;
• 7. Participate in other clinical research in the past three months; previously treatment with any gene therapy products;