As an immune checkpoint blockade, programmed cell death-1 (PD-1) inhibition has achieved a good effect on patients with EBV-positive NK/T lymphoma and gastric cancer.[6,7] Currently, there is evidence that the PD-1 antibody has an obvious curative effect on relapsed/refractory EBV-associated HLH. Here, PDCD1 is linked to hemophagocytic syndrome.