**Abstract**

The management of hepatocellular carcinoma (HCC) has been transformed by the incorporation of immune checkpoint inhibitor therapy. Compared to traditional chemotherapy, these regimens have markedly improved outcomes in patients with HCC. Additionally, they are generally well-tolerated in patients with impaired hepatic function. This chapter will review the landmark trials which have paved the way for the use of ICIs in the treatment of HCC and summarize current consensus on best practices regarding their use in this setting. It will also discuss other prospective uses of immunotherapy for the treatment of HCC currently being investigated, including further incorporation of both checkpoint inhibitor and non-checkpoint inhibitor agents into treatment strategies. Furthermore, it will summarize the existing safety and efficacy data regarding the use of checkpoint inhibitors in patients who have previously undergone liver transplant.

**Keywords:** hepatocellular carcinoma, checkpoint inhibitor therapy, nivolumab, pembrolizumab, sorafenib, Lenvatinib, liver transplant, liver rejection
