Colorectal cancer (CRC) ranks third and second among the most widespread cancers worldwide and the most common causes of human death due to cancer, respectively. Further, for unknown reasons, numbers of young patients diagnosed with colon cancer has increased. Polysaccharides are important functional phytochemicals reported to have anti-CRC effects. Moreover, CRC development and progression is closely related to the gut microbiome. Although approaches for treating CRC have been the subject of some review papers, research into traditional Chinese medicine (TCM) treatments for CRC and the underlying mechanisms involving polysaccharides have not been reviewed. Here, we reviewed the mechanisms underlying treatment of CRC using TCM polysaccharides, based on the etiology of CRC, and common treatment methods applied. The relationship between intestinal microbes and CRC, the mechanism by which TCM polysaccharides induce CRC cell apoptosis, and how TCM polysaccharides promote immune responses are discussed, as well as TCM polysaccharide use in combination with chemotherapy. TCM polysaccharides provide options for CRC treatment, due to their advantages of having multiple targets, eliciting modest adverse reactions, and wide range of available sources.