Here, we show that lymphoma samples contain cytotoxic CD4+ T cells, which were predominantly NKG7/TIA-1+GZMK+ TFH-like in FL and TIA-1+GZMK+ and/or GZMB+ within the CXCR5+PD-1+ and CXCR5–PD-1+ subpopulations of DLBCL. Here, GZMK is linked to diffuse large B-cell lymphoma.