Our results showed that the proportion of CD8 + T cells were higher in low-risk group, and the expressions of CD48, CTLA4, HHLA2, TNFSF9 and TNFSF15 in high-risk group were higher than those in the low-risk group, which suggested that the poor prognosis of HCC patients in high-risk group might be related to the immunosuppressive microenvironment. This evidence concerns the gene HHLA2 and hepatocellular carcinoma.