ObjectiveTo investigate feasibility, safety, and problems to be solved in treatment with programmed death receptor protein-1 (PD-1) monoclonal antibody for patients with recurrent liver cancer after liver transplantation (LT).MethodAll of the domestic and foreign cases reports about the application of PD-1 monoclonal antibody in the patients with recurrent liver cancer after the LT were analyzed and summarized.ResultsIn six patients with recurrent liver cancer after the LT who received the PD-1 monoclonal antibody, the acute graft rejections were observed in 3 patients, 2 patients had the progressive disease but there was no evidence of the graft rejection, 1 patient achieved the complete response and there was no evidence of graft rejection and no side effects.ConclusionsAt present, effect of PD-1 monoclonal antibody therapy is still not sure in patients with recurrent liver cancer after LT. If PD-1 monoclonal antibody is used off-label, close surveillance is needed to discovery possible acute graft rejection.