Prostate cancer（PCa）is most common among American and European elder males. Despite hav⁃ ing the initial effectiveness of radical surgery and androgen deprivation therapy at the preliminary stage，prostate cancer eventually develops into castration⁃resistant prostate cancer（CRPC），which results in a poor prognosis. In recent years，base⁃PD⁃1 inhibitor pembrolizumab has been successfully applied in treating multiple solid tumors， which also has achieved primary efficacy in treating CRPC. This paper summarizes the current status and existing problems of pembrolizumab in the clinical trials of CRPC.