• Aged between 15 and 75 years old, regardless of gender;

• Diagnosed with relapsed/refractory B-cell lymphoma according to the 2020 World Health Organization (WHO) diagnostic criteria;

• Eastern Cooperative Oncology Group (ECOG) performance status score of 0-2;

• Expected survival time of ≥ 3 months;

• Confirmation of CD20 expression in tumor cells by flow cytometry/immunohistochemistry;

• Patients tolerant to CD19 CAR-T cell therapy or those with low CD19 expression;

• No severe heart, lung, liver, or kidney diseases;

• Capable of understanding and willing to sign the informed consent form for this trial;

• No contraindications to peripheral blood apheresis for the subject;

⁃ Having clearly measurable and evaluable lesions according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 standard;

⁃ The subject must have received standard first- and second-line treatment regimens;

⁃ Not having received antibody-based drug treatment within 2 weeks before cell therapy.