Objective To investigate the association between intestinal microbiota dysbiosis and colonic polyps， Helicobacter pylori （Hp） infection， and intestinal metaplasia. Methods A total of 200 patients diagnosed with colonic polyps， Hp infection， or both conditions. These patients were classified into three groups： the colonic polyp group （n = 90）， the Hp infection with intestinal metaplasia group （n = 49）， and the colonic polyp combined with Hp infection and intestinal metaplasia group （n = 61）. Additionally， 62 individuals who underwent routine health examinations at our hospital during the same period were enrolled as a control group. The study compared gut microbiota imbalances across these groups to investigate the association between intestinal dysbiosis and colonic polyps， Hp infection， and the co?occurrence of colonic polyps with Hp?related intestinal metaplasia. Logistic regression analysis was performed to identify risk factors associated with the development of intestinal metaplasia due to Hp infection in patients with colonic polyps. Results Compared to the control group， intestinal flora imbalance was significantly more prevalent in the colorectal polyp group， the Hp infection with intestinal metaplasia group， and the colorectal polyp combined with Hp infection and intestinal metaplasia group （P < 0.05）. Moreover， intestinal flora imbalance in the colorectal polyp with Hp infection and intestinal metaplasia group was significantly higher than that in both the colorectal polyp group and the Hp infection with intestinal metaplasia group （P < 0.05）. Regarding exhaled gas levels， H₂ and CH₄ concentrations were significantly elevated in the groups with colorectal polyps accompanied by Hp infection and intestinal metaplasia， those with colorectal polyps alone， and those with Hp infection and intestinal metaplasia， compared to the control group （P < 0.05）. Similarly， exhaled H₂S levels were significantly higher in the group with colorectal polyps complicated by Hp infection and intestinal metaplasia than in the control group （P < 0.05）. Furthermore， exhaled H₂ and CH₄ levels showed positive correlations with the presence of colorectal polyps， Hp infection with intestinal metaplasia， and colorectal polyps combined with Hp infection and intestinal metaplasia （P < 0.05）. Exhaled H₂S levels were positively correlated with colorectal polyps complicated by Hp infection and intestinal metaplasia （P < 0.05）. Logistic regression analysis indicated that a history of smoking， atrophic gastritis， peptic ulcer， and intestinal flora imbalance are independent risk factors for Hp infection-associated intestinal metaplasia in patients with colorectal polyps （P < 0.05）. Conclusion Intestinal flora imbalance is associated with colorectal polyps and Hp?induced intestinal metaplasia， suggesting that microbial dysbiosis may represent a potential risk factor for the development of these conditions.