Hepatocellular carcinoma (HCC) is currently the third leading cause of cancer mortality and a common poor-prognosis malignancy due to postoperative recurrence and metastasis. There is a significant correlation between chronic hepatitis B virus (HBV) infection and hepatocarcinogenesis. As the first line of host defense against viral infections and tumors, natural killer (NK) cells express a large number of immune recognition receptors (NK receptors (NKRs)) to recognize ligands on hepatocytes, liver sinusoidal endothelial cells, stellate cells and Kupffer cells, which maintain the balance between immune response and immune tolerance of NK cells. Unfortunately, the percentage and absolute number of liver NK cells decrease significantly during the development and progression of HCC. The abnormal expression of NK cell receptors and dysfunction of liver NK cells contribute to the progression of chronic HBV infection and HCC and are significantly associated with poor prognosis for liver cancer. In this review, we focus on the role of NK cell receptors in anti-tumor immune responses in HCC, particularly HBV-related HCC. We discuss specifically how tumor cells evade attack from NK cells and how emerging understanding of NKRs may aid the development of novel treatments for HCC. Novel mono-and combination therapeutic strategies that target the NK cell receptor-ligand system may potentially lead to successful and effective immunotherapy in HCC. Keywords: activating receptor; hepatocellular carcinoma; inhibitory receptor; natural killer cell; natural killer receptor INTRODUCTION Hepatocellular carcinoma (HCC) is currently the third leading cause of cancer mortality and a common poor-prognosis malignancy due to postoperative recurrence and metastasis. 1 Common clinical risk factors for HCC include hepatitis B virus (HBV)/hepatitis C virus (HCV) infection, heavy alcohol intake, steatohepatitis and diabetes. 2 Approximately 50% of HCC cases worldwide can be attributed to chronic HBV infection (CHB) and almost 75% of HCC cases occur in developing countries where HBV is endemic. 3,4 According to statistics, older male patients who are infected with HBV genotype C or co-infected with HCV, have high levels of viral load and have been exposed to the aflatoxin, or older male patients who have a family history of HCC tend to have a high risk of developing HCC. [5][6][7] Accumulating clinical and epidemiological evidence shows a significant correlation between chronic HBV infection and hepatocarcinogenesis. However, the underlying mechanisms