Abstract: Objective To analyze the relationship of B7-H3 expression in human esophageal squamous cell carcinoma (ESCC) and clinicopathological parameters as well as overall survival in ESCC patients. Methods Immunohistochemical assay was applied to evaluate the expression of B7-H3 and the intensity of tumor infiltrating CD8+T lymphocytes in 82 cases of ESCC tissues, corresponding adjacent tissues and esophageal squamous atypical hyperplasia tissues. Results B7-H3 expression was found in 98.8% (81/82) of ESCC tissues, while it was almost negative in adjacent tissues and atypical hyperplasia tissues. The abnormal expression of B7-H3 was correlated with age, tumor grade and TNM stage (P<0.05). Meanwhile, B7-H3 expression was negatively correlated with the intensity of tumor infiltrating CD8+T lymphocytes and postoperative prognosis (P<0.05). Conclusion B7-H3 is overexpressed in ESCC tissues, which is closely correlated with tumor stage. Moreover, B7-H3 overexpression could reflect CD8+T cell infiltration and may help tumor cells avoid immune surveillance. Therefore, B7-H3 plays significant roles in diagnosis, targeted therapeutics and prognosis.