Abstract: Metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) have become severe complications in patients with obesity and overweight.Liver fibrosis is a major characteristic of MASLD and may progress to cirrhosis or hepatocellular carcinoma.Bariatric surgeries, such as Roux-en-Y gastric bypass and sleeve gastrectomy, have gradually become optional treatments for improving obesity and MASLD.However, the mechanisms by which bariatric surgery improves liver fibrosis still need further exploration.This article explores the mechanisms by which gut microbiota after bariatric surgery exert direct or indirect therapeutic effects on liver fibrosis through maintaining gut barrier function, regulating metabolic function, and influencing the immune system.

Key words: bariatric surgery; intestinal flora; hepatic fibrosis