Abstract: Objective: To learn more about the effects of oncogene mdm2 on colon cancer. Methods: MDM2 protein expression was evaluated in the tissues of 93 cases with colorectal cancer by immunohistochem-istry analysis.The relationship between clinicopathologic features and expression of MDM2 and P21proteins were studied. Results: High MDM2 protein expression in colorectal carcinoma was signifi-cantly associated with late TNM stage. An positive relationship of MDM2 with P21 expression was ob-served (Pearson correlation co-efficient P=0.023,r=0.210). The univariant analysis showed high expres-sion of MDM2 、 low expression of P21 expression and therapy were significantly correlated with poor survival (P<0.05). The multivariant analysis revealed that MDM2 expression is an independent prognos-tic factor for survival in colorectal carcinoma, and the patients with both a higher expression of MDM2 、TNM stage and distant metastasis showed a significantly unfavorable prognosis. Conclusions: Our re-search indicated that mdm2 gene played a definite role in cell proliferation of cancer cells. mdm2 oncogene might play important roles in the development and aggressiveness of human colorectal carci-noma. It may be taken to calculate the biological behavior and the prognosis of human colon cancer.