Due to the difficulty in early diagnosis and the lack of treatment for advanced disease, the mortality rate of hepatocellular carcinoma (HCC) is high, and the 5-year overall survival rate is low at present. SLC1A4 is a neutral amino acid transporter, but its regulatory role and mechanism in HCC are still unclear. Through analyzing the TCGA database and clinical tissue specimens, this study uncovered the high expression of SLC1A4 in tumor tissues of HCC. Worse more, a high level of SLC1A4 may lead to a poor prognosis of HCC. Mechanically, silencing SLC1A4 inhibited the phosphorylation activation of AKT by suppressing the ubiquitin modification of AKT at lysine 63 and amino acid influx represented by D-serine, decreasing the protein level of