<p>Colorectal cancer ranks among the most prevalent malignancies globally, with its incidence strongly correlated with human development indices, presenting a major public health challenge. The gut microbiota and their metabolites play crucial roles in colorectal cancer pathogenesis. Recent advances in understanding tumor microenvironment immunology during cancer progression and treatment have highlighted the significant impact of the gut microbiota on tumor immunity. This review synthesizes current evidence on the complex interactions between gut microbiota, their metabolites, and colorectal cancer development, while examining the mechanisms through which microbial communities and their metabolic products contribute to carcinogenesis. Furthermore, we assess the clinical potential of microbiota-based biomarkers for colorectal cancer diagnosis. Our analysis aims to explore innovative therapeutic approaches through microbiota modulation for colorectal cancer prevention and treatment, potentially revealing novel mechanisms to combat this devastating disease.</p>