Inclusion Criteria:  ≥ 18 years old; Sign on the informed consent; Subject must have histologically confirmed diffuse large B lymphoma and primary refractory with first-line therapy; Subjects have accessible PET-positive lesion and have measurable CT-positive lesion according to Lugano Classification; Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1; Adequate organ function; Adequate vascular access for leukapheresis procedure; Subjects who have previously received CD19 targeted therapy must confirm that lymphoma lesions still express CD19; Women of childbearing potential must agree to use highly effective methods of contraception for 1 year after the last dose of JWCAR029; Males who have partners of childbearing potential must agree to use an effective barrier contraceptive method for 1 year after the last dose of JWCAR029  Exclusion Criteria:  Subjects who have received second-line treatment or above CD19 negative Primary CNS lymphoma; History of another primary malignancy that has not been in remission for at least 2 years; Subjects has HBV, HCV, HIV or syphilis infection at the time of screening; Deep venous thrombosis (DVT)/Pulmonary embolism (PE), or DVT/PE requires anti-coagulation within 3 months prior to signing the ICF; Subjects with uncontrolled systemic fungal, bacterial, viral or other infection; Presence of acute or chronic graft-versus-host disease (GVHD); History of any serious cardiovascular disease or presence of clinically relevant CNS pathology; Pregnant or nursing women; Subjects using of any chemotherapy, corticisteriod, experiment agents, GVHD therapies, radiation, allo-HSCT or any other therapies for lymphoma must go through a specific wash-out period before leukapheresis; Uncontrolled conditions or unwillingness or inability to follow the procedures required in the protocol; Received CAR T-cell or other genetically-modified T-cell therapy previously.