• The subject is willing to sign the informed consent form (ICF) after comprehensive understanding;

• Age ≥18 years and ≤75 years, both male and female;

• The pathology was confirmed as diffuse large B-cell lymphoma according to the 2016 World Health Organization classification definition;

• Evaluation by Positron Emission Computed Tomography (PET-CT) or Computed Tomography (CT) or Magnetic resonance imaging (MRI) using Lugano 2014 standard, with measurable lesion injection;

• Must have recurrent or refractory diffuse large B-cell lymphoma after at least 1 systemic therapy, and at least 1 systemic therapy included CD20 antibody;

• Eastern Cooperative Oncology Group (ECOG) scores 0-2 points;

• Life expectancy \>12 weeks;

• The level of organ function must meet the following requirements:

⁃ Peripheral blood:

• Absolute neutrophil count (ANC) ≥1000/μL;

• Hemoglobin (HGB) ≥8g/dL;

• Platelet count (PLT) ≥100,000/μL;

⁃ Liver function:

• Serum total bilirubin ≤1.5×ULN (for patients with Gilbert syndrome, total bilirubin \<3.0×ULN and Direct bilirubin within normal range);

• Serum creatinine \<1.5×ULN;

• ALT, AST or ALP≤2.5×ULN (≤5×ULN when liver involvement occurs).