Inclusion Criteria:  Aged ≥ 18 years and <70 years. Expected survival over 6 months. Eastern Cooperative Oncology Group score≤ 2. Diagnosed pathologically and histologically CD19+B cell lymphoma, including mantle cell lymphoma, chronic lymphocytic leukemia, follicular cell lymphoma, Burkitt lymphoma and diffuse large B cell lymphoma. Patients have failed at least 1 line of prior therapy Negativity of blood pregnancy test for woman, and participants use effective methods of contraception until last follow-up.  Patient or his or her legal guardian voluntarily participates in and signs an informed consent form.  -  Exclusion Criteria:  Investigators judge the patients with gastrointestinal lymph node and/or central nervous system involvement who may be at high-risk of receiving CAR-T-CD19 cell treatment. Existing or preexisting CNS conditions, such as epileptic seizures, cerebrovascular ischemia/hemorrhage, dementia, cerebellar disease, or any CNS related autoimmune diseases. Patients with graft-versus-host reaction and need immunosuppressive agents, or patients with autoimmune diseases. Participants with other active malignancies (except non-melanoma skin cancer and cervical cancer) within five years. History of Richter's syndrome. History of any one of the following cardiovascular conditions within the past 6 months: Class III or IV heart failure as defined by the New York Heart Association (NYHA), cardiac angioplasty or stenting, myocardial infarction, unstable angina, or other clinically significant cardiac disease. Patients who are pregnant or breast-feeding.  Patients with any one of the following terms:  A. Creatine >2.5mg/dl (221.0umol/L). B. Alanine aminotransferase/aspartate aminotransferase >3 times the upper limit of normal (ULN).  C. Total bilirubin>2.0 mg/dl (34.2umol/L).  Major surgery within 4 weeks of randomization. Systemic steroids are used within 2 weeks before apheresis (Except for those who are using inhaled steroids recently or currently). Patients receive cytotoxic chemotherapy or radiotherapy within 21 days before enrollment (Tyrosine kinase inhibitors or other targeted therapies can be used two weeks before lymphodepleting chemotherapy). Prior treatment with any gene therapy product. Active hepatitis B, active hepatitis C, or active human immunodeficiency virus (HIV) infection. Systemic fungal, bacterial, viral, or other infection that is not controlled. The absolute value of lymphocytes was too low to manufacture CAR-T cells.  Other conditions considered inappropriate by the researcher.  -