Colorectal cancer is one of the most common gastrointestinal tumors with good outcomes, but when it has distant metastasis, the outcomes turn to be poor. Novel treatment methods are eager to develop. Our in vitro studies demonstrate that dual-specificity tyrosine-regulated kinase 2 (DYRK2) functions as a tumor suppressor in colorectal cancer by regulating cell survival, proliferation, and apoptosis induction. In addition, DYRK2 expression is decreased in tumor tissues compared to non-tumor tissues in colorectal cancer, indicating a correlation with clinical prognosis. In this context, we devise a novel therapeutic strategy to overexpress DYRK2 in tumors by the adenovirus-mediated gene transfer. The present study shows that overexpression of DYRK2 in colon cancer cell lines by adenovirus inhibits cell proliferation and induces apoptosis in vitro. Furthermore, in mouse subcutaneous xenograft and liver metastasis models, enforced expression of DYRK2 by direct injection or intravenous administration of adenovirus to the tumor significantly inhibits tumor growth. Taken together, these findings demonstrate that adenovirus-based overexpression of DYRK2 may be a novel gene therapy for liver metastasis of colorectal cancer.