In this study, we show that higher pretreatment PNR is associated with increased CR rate and longer PFS after anti‐PD‐1‐based immunotherapy in R/R cHL, and further highlighted the prognostic value of the novel indicator—PNR—in cases with solid tumor after anti‐PD‐1 combination therapy. This evidence concerns the gene PDCD1 and classic Hodgkin lymphoma.