The present disclosure relates to a composition for diagnosis of liver metastasis of colorectal cancer and the use thereof, and more particularly to a composition for diagnosis of liver metastasis of colorectal cancer, which comprises either a substance for measuring the mRNA level of CCL7 (Chemokine (C-C motif) ligand 7) gene or a substance for measuring the level of a protein which is encoded by the gene. According to the present disclosure, whether liver metastasis of colorectal cancer occurred can be diagnosed by measuring the mRNA expression level of the CCL7 gene or the expression level of the CCL7 protein, and the use of the composition comprising an inhibitor of CCL7 gene allows the treatment of colorectal cancer or the liver metastasis of colorectal cancer.