Objective: To observe the expression of DNA-dependent protein kinase (DNA-PKcs) in the nasopharyngeal tissues during carcinogenesis. Methods: Patients including 30 cases of nasopharyngitis, 42 cases of nasopharyngeal atypical hyperplasia and 34 cases of nasopharyngeal carcinoma (NPC) were chosen from Zhongshan area in which there is high incidence rate of NPC. The expression of DNA-PKcs in the nasopharyngeal tissue was examined by immunohistochemistry. Results: The expression rates of DNA-PKcs in the nasopharyngitis tissue, the nasopharyngeal precancerous lesion and the NPC were 6.7%, 64.3% and 55.9%, respectively (P〈 0.001). Conclusion: The expression of DNA-dependent protein kinase may play an important role in nasopharyngeal tissue carcinogenesis.