Objective To investigate whether CD19-CAR T cells co-expressing PD-1 /ICOS signal transforming receptor can induce stronger antitumor activity against diffuse large B-cell lymphoma. Methods CD19-CAR T cells (bbz) and CD19-CAR T cells coexpressing PD-1/ICOS signal transforming receptor (PD1/ICOS-bbz) were constructed by lentivirus infection. The expression of CD69 on T cells after longterm coincubation was detected by flow cytometry. The proliferation of CAR T cells was detected by cell count. LDH assay was used to detect the cytotoxicity of CAR T cells against target cells. In vivo imaging was used to detect the growth of tumor cells in mice. The proportion of T cells in peripheral blood was detected by flow cytometry. Results bbz and PD-1/ICOS-bbz were constructed successfully. After long-term co-incubation, CD69 expression level of PD-1/ICOS-bbz was higher than that of bbz (P＜0.001), and proliferation ability (P＜0.01) and cytotoxicity to target cells (P＜0.01) were also significantly improved. PD-1/ICOS-bbz can completely eliminate lymphoma cells in mice, and PD-1/ ICOS-bbz can significantly prolong the survival period of mice compared with bbz (P＜0.01). PD-1/ICOS-bbz has a stronger in vivo proliferation ability than bbz. Conclusion PD-1/ ICOS-bbz has stronger antitumor activity than conventional second-generation CAR T cells, and may be a promising treatment option for potential diffuse large B-cell lymphoma.