Abstract: Colorectal cancer (CRC), the most common malignant tumor of the digestive system with the highest morbidity and mortality worldwide, has received increasing attention for its relationship with the gut microbiota. The gut microbiota interacts with the host cells to regulate various physiological processes, including metabolism and immune responses. Recently, increasing research has revealed that the interaction between the host and gut microbiota plays a significant role in the origin and progression of CRC. In this review, we discuss the specific mechanisms of the gut microbiota involvement in the carcinogenesis, invasion, and metastasis of CRC, as well as its impact on the therapeutic response and prognosis, by describing the gut and intratumoral microbiota associated with CRC. This information serves as a reference for understanding the relationship between gut microbiota and CRC, and provides therapeutic ideas for the development of microbiota-based interventions for CRC treatment.