In recent years, immunotherapy represented by immune checkpoint inhibitors (ICIs) has created new opportunities for conversion therapy in intermediate to advanced hepatocellular carcinoma (HCC). The combination of ICIs with locoregional treatments, such as transcatheter arterial chemoembolization and hepatic arterial infusion chemotherapy, has demonstrated significant advantages in improving tumor response rates and eliciting systemic immune reactions, markedly enhancing the conversion rate of HCC compared to traditional approaches. However, the application of ICIs prior to liver transplantation also brings potential safety concerns, particularly the risk of graft rejection. These risks are exacerbated by the lack of standardized drug withdrawal intervals and the unpredictability of donor liver allocation, posing substantial challenges in clinical practice. This article systematically reviews the current status of ICIs in downstaging treatment prior to liver transplantation for HCC and discusses risk management strategies, aiming to provide reference for clinical decision-making and guideline development.