In this study, we aimed to investigate the therapeutic effects and involved mechanisms of resveratrol on an established non-alcoholic fatty liver disease (NAFLD) murine model. Wild-type and autophagic mediator ULK1 heterozygous knockout mice were induced to have NAFLD by high-fat diet for 8 weeks. After that, resveratrol treatment was applied with the high-fat diet feeding for another 4 weeks. Typical features of NAFLD, including histological changes, fibrosis, insulin resistance, oxidative status, and inflammation were characterized. After-treatment with resveratrol showed ameliorative effects on all measured features of NAFLD, from histology, insulin resistance, glucose tolerance to oxidative stress and inflammation. resveratrol treatment also reduced the activity of nuclear factor-κB (NF-κB) through the restoration of its inhibitor IκBα. Partial inhibition of ULK1 expression impaired the ameliorative effects of resveratrol on hepatic histology, fibrosis, oxidative status, inflammation, and NF-κB activity. In conclusion, resveratrol improved NAFLD-caused hepatic injury partially through regulating autophagic and IκBα-NF-κB pathways.