Epstein-Barr virus (EBV) is closely related to the occurrence and development of nasopharyngeal carcinoma. The quantitative detection of Epstein-Barr virus DNA (EBV DNA) in plasma from the patients with nasopharyngeal carcinoma using the polymerase chain reaction (PCR)-based strategies can effectively evaluate the response to treatments and predict the risk of recurrence and metastasis. The pre-treatment EBV DNA base line is in accordance with the tumor load, and the post-treatment EBV DNA levels can predict the recurrence and metastasis of the nasopharyngeal carcinoma. It would be a new tumor-maker. This article briefly reviewed the application of plasma EBV DNA from different phases of nasopharyngeal carcinoma patients in the diagnosis, evaluation, monitoring and prognosis-prediction.