In the treatment of Hodgkin lymphoma (HL), it is important to avoid delayed side effects while improving efficacy, the immunotherapy provides an excellent option. The programmed death receptor 1 (PD-1) inhibitors are effective drugs for the treatment of relapsed/refractory HL. Meanwhile, the high effectiveness and tolerance of PD-1 inhibitors also provide the possibility for combination therapy. This article reviews the research progress of PD-1 inhibitors in the treatment of relapsed/refractory HL.