In this study, we demonstrated that the treatment of colorectal cancer with the thermo-chemotherapeutic treatment composed of magnetic hyperthermia and 5FU-MNP-based chemotherapy was much more effective and led to a better therapeutic outcome in tumor bearing mice than magnetic hyperthermia or 5FU-MNP-based chemotherapy alone, as reflected by the distinctly reduced tumor volume and inhibited tumor cell proliferation (i.e., Ki67 protein expression). This evidence concerns the gene MKI67 and colorectal cancer.