In this study, we took advantage of data from The Cancer Genome Atlas (TCGA) to analyse: (1) the content of immune cells and stromal cells infiltrating the tumour microenvironment of HCC; (2) the relationship between immune scores and prognosis; (3) the relationship between immune scores and TP53, CTNNB1, and AXIN1 mutations; and (4) immune microenvironment-related genes and their impact on prognosis. This evidence concerns the gene TP53 and hepatocellular carcinoma.