【Abstract】ObjectiveTo detect the expression of melanoma antigen-3 gene (MAGE-3) in rectal cancer and explore its relationship with the clinical pathology of rectal cancer and clinical significance in immune therapy. MethodsThe expressions of MAGE-3 in tumor tissue, para-tumor tissue of （5±1） cm from border of tumor tissue, tissue of resection border and polypus were detected by RTPCR. ResultsMAGE-3 expression was positive in 14 of 33(42.42%) samples of rectal cancer, 6 of 33 (18.18%) of paratumor tissue, and 5 of 33 (15.15%) of resection border tissue respectively. No MAGE-3 was detected in 3 polypi. The positive rate of MAGE-3 in tumor tissue was significantly higher than that of the paratumor and resection border tissue (P＜0.05). The expression of MAGE-3 was not related to age, gender, histological type, metastasis to lymph nodes, and Dukes stage (Pgt;0.05). Conclusion MAGE-3 protein may be used as a target of immunotherapy for rectal cancer and an index for follow-up and screening of rectal cancer.