〔Abstract〕 Liver cancer is the sixth most common type of cancer worldwide and the third leading cause of cancer-related deaths. Approximately 30% of patients are diagnosed at an early stage of liver cancer, at which point curative treatments such as partial liver resection and liver transplantation can be performed, leading to a median overall survival exceeding 60 months. However, most patients are diagnosed at an advanced stage of liver cancer, where treatment options often include targeted therapies and immune checkpoint inhibitors. Systemic treatments including immune checkpoint inhibitors play a crucial role in significantly improving the prognosis of patients with advanced liver cancer. Therefore, in-depth exploration of the immune microenvironment characteristics of liver cancer and active identification of biomarkers for immunotherapy are crucial to advancing and improving immunotherapy for liver cancer.