Artesunate (ART) is a water-soluble derivative of artemisinin, which has shown anti-inflammatory, anti-tumor, and immunomodulating effects. We aimed to investigate the potential therapeutic effects and mechanisms of ART in metabolic dysfunction-associated steatohepatitis (MASH). The mice were randomly divided into the control group, high-fat, high-cholesterol diet-induced MASH group, and the MASH treated with ART (30 mg/kg once daily) group. Liver enzymes, lipids, and histological features were compared among groups. The molecular mechanisms were studied by transcriptomic and lipidomics analyses of liver tissues. The mice of the MASH group had significantly increased hepatic fat deposition and inflammation in terms of biochemical indicators and pathological manifestations than the control group. The ART-treated group had improved plasma liver enzymes and hepatic cholesterol, especially at week 4 of intervention (p < 0.05). A total of 513 differentially expressed genesand 59 differentially expressed lipids were identified in the MASH group and the MASH+ART group. Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment test showed that ART regulated glycerolipid metabolism pathway and enhanced fatty acid degradation. Peroxisome proliferator-activated receptor (PPAR)-α acted as a key transcription factor in the treatment of MASH with ART, which was confirmed by cell experiment. ART significantly improved fat deposition and inflammatory manifestations in MASH mice, with potential therapeutic effects. The mechanism of artemisinin treatment for MASH may involve extensive regulation of downstream genes by upstream transcription factors, such as PPAR-α, to restore hepatic lipid homeostasis.