Colorectal cancer is one of the most common malignant tumors, liver metastasis is the main factor affecting the prognosis of patients with colorectal cancer. Exosomes as lipid bilayer microvesicles widely existing in a variety of biological fluids, can promote the occurrence and development of colorectal cancer liver metastasis by inducing M2 macrophage polarization, regulating the activity of cancer-associated fibroblasts and enhancing drug resistance of tumor cells, plays an important role in the diagnosis, treatment and prognosis of colorectal cancer liver metastasis. To explore the mechanism of exosomes in colorectal cancer liver metastasis and related treatment progress, in order to find new drug targets to improve the prognosis of patients.