AbstractDiffuse large B cell lymphoma (DLBCL) expresses abundant programmed death ligand 1 (PD‐L1), which shields tumor cells from immune attacks through the PD‐L1/PD‐1 signaling axis. The mechanism of PD‐L1 overexpression includes the deletion of the 3′end ofPD‐L1, which increases its mRNA stability, and the gain or amplification ofPD‐L1. Previous studies found two cases of DLBCL carrying anIGH::PD‐L1by whole genome sequencing. We describe two more such cases by a targeted DNA next‐generation sequencing (NGS) capable of detectingIGHrearrangements, leading toPD‐L1overexpression. DLBCL with PD‐L1 overexpression is often resistant to R‐CHOP (rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine and prednisolone). Our patients responded to a combination of R‐CHOP and a PD‐1 inhibitor.