The prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is increasing annually, which is a global public health issue. Although clinical trials are lacking, observational studies indicate that bariatric surgery can alleviate the progression of MASH. Here, we performed sleeve gastrectomy (SG) and Sham surgery on 8-week-old mice, and then fed a AMLN diet for 24 weeks to construct a diet-inducted MASH mice model after 4-week post-surgery recovery. Applying a multi-omics approach combining metagenomics, metabolomics, and transcriptomics, we found that SG prevents the development of hepatic steatosis, inflammation, and fibrosis in MASH mice not only by significantly altering the structure of gut microbiota including s_Akkermansia muciniphila, s_Alistiples dispar, g_Helicobacter and s_uc_Oscillospiraceae, but also by modulating the levels of serum metabolites including l-arginine and taurocholic acid (TCA). These results suggest that SG and the alteration of gut microbiota and its related serum metabolites can be served as the effective therapeutic strategies for MASH.