In the conducted research, a murine model for ulcerative colitis (UC) was established utilizing dextran sodium sulfate (DSS) to investigate the therapeutic potential of dandelion root polysaccharide extracts on this disease. This study employed an analysis of gut microbiota composition and serum metabolomics to understand the biochemical effects of these polysaccharides. Sequencing of the 16S ribosomal DNA component indicated an increased presence of Bacteroides in the DSS-treated model group, contrasting with a significant enhancement in Faecalibaculum populations in mice treated with dandelion root polysaccharides (DPs). This shift suggests a pivotal role of DPs in elevating fecal N-butyric acid levels-a crucial factor in the maintenance of gut microbiota equilibrium. Through metabolomic profiling of serum, this research identified distinct metabolic changes across the control, DSS model, and DP treatment groups, highlighting four major differential metabolites: (2S)-2-amino-3-[[(2R)-2-butanoyloxy-3-propanoyloxypropoxy]-hydroxyphosphoryl]oxypropanoic acid; (1R,8S,9S)-3,4-dihydroxy-8-methoxy-11,11-dimethyl-5-propan-2-yl-16-oxatetracyclo [7.5.2.01,10.02,7]hexadeca-2,4,6-trien-15-one; Aspartylasparagine; and Nap-Phe-OH. These metabolites are implicated in mitigating oxidative stress, suggesting that DPs facilitate a protective mechanism for the intestinal lining through various biochemical pathways. Additionally, a notable correlation was established between the altered gut microbiota and the serum metabolomic profiles, underscoring the intricate interplay between these two biological systems in the context of UC. This study's outcomes illustrate that UC induces significant alterations in both gut microbiota and metabolic signatures, whereas dandelion root polysaccharides exhibit a profound ameliorative effect on these disruptions. This investigation underscores the therapeutic promise of dandelion root polysaccharides in the management of UC by modulating gut microbiota and metabolic pathways.