Description:The aim of this study was to investigate the relationship between gut microbiota, metabolites and scar hypertrophy using the rabbit ear hypertrophic scar model. On postoperative day 28, the rabbits were divided into scar-susceptible (group H) and scar-insusceptible (group L) groups according to macroscopic scar thickness. Using fecal microbiota transplantation (FMT), we exchanged the gut microbiota of group H and group L. Untargeted metabolomics was performed before and after FMT. We found that in the rabbit ear hypertrophic scar model, scar hypertrophy was more severe in group H and was associated with fecal microbiota and their metabolites. Gut microbiota components and key genera were transferred between group H and group L by FMT, accompanied by altered levels of key metabolites such as TCDCA (bile acid taurochenodeoxycholic acid). FMT relieved scar hypertrophy in group H and vice versa. TCDCA were decreased in group H rabbit and its relative abundance was successfully reversed by heterochronic FMT.