Background and Purpose: Although the prevalence of nonalcoholic steatohepatitis (NASH) is rapidly increasing, effective therapy is lacking. Tenofovir alafenamide (TAF) is a widely used antiviral drug for hepatitis B. In this study, we investigated the potential pharmacological effects of TAF on NASH. Experimental Approach: Two different NASH mouse models were established: 1) by subcutaneous injection of streptozotocin (0.2 mg) and feeding the mice a high-fat, high-cholesterol (HFHC) diet, and 2) feeding the mice a choline-deficient, L-amino acid-defined, high-fat (CDAHF) diet. Key Results: Serum alanine aminotransferase and triglyceride levels in TAF-treated NASH mice were significantly lower than those in the mock-treated ones. The livers from the TAF-treated NASH mice showed attenuated mononuclear phagocyte (MP) infiltration compared to those from the mock-treated ones. TAF-treated NASH mice exhibited decreased liver infiltration of activated MPs (IAIE+/PD-L1+/MerTK+). In ex vivo experiments using sorted human CD14+ monocytes treated with lipopolysaccharide (LPS) and/or TAF, we confirmed the decreased level of phosphorylated AKT in TAF-treated LPS-stimulated monocytes compared to that in the mock-treated ones. Mouse liver immunoblotting showed that phosphorylation levels of AKT were significantly lower in the TAF-treated NASH group than in the mock-treated group. Conclusion and Implications: TAF exerts anti-inflammatory effects in NASH livers by attenuating AKT phosphorylation in intrahepatic activated MPs. Therefore, TAF may serve as a new therapeutic option for NASH.