Abstract: ObjectiveTo study the relationship between the expression of gap junction proteins connexin26 and connexin43 and the occurence，invasion and metastasis of esophageal squamous cell carcinoma. MethodsThe expression of Cx26 and Cx43 proteins and mRNA were detected by SP immunohistochemical and RT-PCR methods in 42 cases of esophageal squamous cell carcinoma (EC) tissue,17 cases of mucosa adjacent to cancer and 42 cases of normal esophageal mucosa. ResultsThe positive expressions of Cx26, Cx43 protein and mRNA in cancer tissue were both lower than that in normal mucosa tissue, and the positive expression of Cx26, Cx43 protein in tumor-adjacent atypical hyperplasia epithelium had a decreasing trend. Cx26, Cx43 gene loss or decreased expression had closely correlation with invasion depth and lymph node metastasis of esophageal squamous cell carcinoma. There was a correlation between the expression of Cx26, Cx43 protein and differentiation levels of tumor, and positive correlation between the expression of Cx26,Cx43 protein and the expression of Cx26, Cx43 mRNA. ConclusionConnexin26 and connexin43 can provide a theoretical basis to suppress of carcinogenesis, invasion and metastasis of esophageal squamous cell carcinoma and may be used for early diagnosis, invasion and metastasis of esophageal squamous cell carcinoma.