A high hepatitis B virus (HBV) load and chronic hepatitis B infection are well-recognized risk factors for the development of hepatocellular carcinoma (HCC), highlighting the need for research into the mechanisms underlying the role of HBV infection in HCC. Because phosphatase and tensin homolog (PTEN) has been implicated in HCC development, we explored whether PTEN has a role in HBV-related hepatocarcinogenesis. We found that PTEN expression was correlated with advanced clinicopathological features and that HBV infection exacerbates PTEN defects in HCC. Using an integrated approach, we then investigated if miRNAs linked HBV infection to PTEN downregulation in HCC and found that PTEN was a target of miR-181a/382/362/19a. We also show that miR-181a/382/362/19a-mediated inhibition of PTEN led to an enhanced malignant phenotype and stimulation of AKT signaling in HCC cells. Collectively, our results indicate that HBV infection exacerbates PTEN defects in hepatocellular carcinoma through upregulation of miR-181a/362/382/19a. Our work implicates miR-181a/362/382/19a and PTEN as potential biomarkers and targets for novel prognostic, diagnostic, and therapeutic strategies targeting HBV-related HCC.