Inclusion Criteria:  Subjects with a histopathological or cytologically diagnosis of HCC Subjects who have undergone a curative resection High risk for HCC recurrence as protocol defined No previous systematic treatment and locoregional therapy for HCC Child-Pugh Score, Class A ECOG performance status 0 or 1 Full recovery from surgical resection Adequate organ function Absence of major macrovascular invasion No extrahepatic spread Life expectancy of at least 6 months  Exclusion Criteria:  Known fibrolamellar HCC, sarcomatoid HCC or mixed cholangiocarcinoma and HCC Evidence of residual, recurrent, or metastatic disease Known history of serious allergy to any monoclonal antibody History of hepatic encephalopathy Tumor thrombus in portal vein or superior mesenteric vein or inferior caval vein Portal hypertension with bleeding esophageal or gastric varices within 6 months prior to initiation of treatment Any bleeding or thrombotic disorder within 6 months prior to initiation of treatment Any active malignancy within 2 years prior to the start of treatment Active or history of autoimmune disease Other acute or chronic conditions, psychiatric disorders, or laboratory abnormalities that may increase the risk of study participation Prior therapy with an anti-PD-1, anti-PD-L1, or anti PD-L2 agent or other immunotherapy Pregnant or lactating women