Abstract: Objective To study the expression and signifi cance of PIRH2 and P53 in esophageal squamous cell carcinoma tissues. Methods SP method was used to examine the expression of PIRH2 and P53 in 44 tissues of esophageal squamous cell carcinom, atypical hyperplasia and normal esophageal mucosa. Results (1) Positive expression rates of PIRH2 were 88.64%, 68.18% and 25% in tissues of squamous carcinoma, atypical hyperplasia and normal esophageal mucosa, respectively. There were signifi cant differences between any two groups (P<0.016). Expressions of P53 protein were 43.18%, 38.64% and 0 in tissues of squamous carcinoma, atypical hyperplasia, and normal esophageal mucosa, respectively. There were significant differences between normal esophageal mucosa and other groups (P<0.016).(2) The expression of PIRH2 had no relationship with the differentiation grade of carcinoma,invasion,lymph node metastasis,patient′s age and gender (P>0.05). The expression of P53 protein had no relationship with the differentiation invasion, lymph node metastasis,patient's age and gender (P>0.05), but with signifi cant correlation with the differentiation grade of carcinoma (P<0.05).(3) The expression of PIRH2 had no correlation with P53 in esophageal squamous cell carcinoma tissues. Conclusion The high expression of PIRH2 and P53 protein may play an important role in the development and evolution of esophageal squamous cell carcinoma,to be the new data to make judgment of esophageal carcinoma. PIRH2 could degrade wtP53 and inhibit the activity of wtP53, to promote the occurrence of esophageal squamous cell carcinoma,but without obvious effect on mtP53.