Abstract： Objective To examine the expression of MMP-2 gene and Survivin gene in subclinical microscopic tumor and its peripheral normal esophageal tissues,and study the radiation target in molecular level. Methods Esophageal squamous cancer and its peripheral tissue samples of 34 patients were cut into sequential sections.The expression of MMP-2 gene and Survivin gene then examined.The length of the peripheral esophageal tissue,positively expressing the two genes,was measured,and the relation among the experimental date,tumor stage and vertical length of tumor were analyzed. Results For tumor tissue,subclinical microscopic tumor and the peripheral differentiated normal tissue,the positive expression rate of MMP-2 was 85%,83%and 79%,respectively.The positive expression rate of Survivin was 76%,85%and 85%,respectively.The positive expression level of both MMP-2 and Survivin genes in subclinical microscopic tumor was significantly higher than that in the peripheral differentiated normal tissue(χ2=6.46,P=0.028 and χ2=16.15,P=0.001).The length was 17.2-70.4 mm and 15.0-82.4 mm of cancerous peripheral tissue with positive expression of MMP-2 gene upside and downside of the tumor.The length was＜70 mm in 97% of the samples.For Survivin gene.the length was 3.7-76.4 mm and 16.1-56.3 mm.and was＜70 mm in 96%of the samples.The length of cancerous peripheral esophageal tissue expressing the two genes increased significantly along with tumor stage or tumor length,and there was statistical correlation between the length of tumor and the positive expression ranges of Survivin gene. Conclusions Both MMP-2 gene and Survivin gene are positively expressed in esophageal cancerous peripheral tissue.The range positively expressing the two genes is＜70 mm in more than 96%of the samples,and the length is correlated with the tumor stage.More attention should be paid to the peripheral differentiated normal tissue with positive expression of MMP-2 gene and Survivin gene in esophageal squamous carcinoma.