摘要:Background: Oral lichen planus (OLP) is a chronic immunologic disease. The etiology of OLP is unknown, viral antigens (for example Epstein-Bar virus) have been proposed as etiologic agents. OLP may get transformation to malignancy so re¬search on the presence of EBV in OLP lesions seems to be necessary. The aim of this study was to ascertain if EBV acted as etiologic factor in pathogenesis of OLP. Methods: Tissue specimens of 22 patients with clinical diagnosis and histopathological confirmation of OLP were used as case group. And that of 22 persons without OLP served as control group. Polymerase Chain Reaction (PCR) method was used. Each sample was tested twice. Results: All biopsy specimens from patients and controls were negative for EBV presence. Conclusions: In spite of the fact that the presence of EBV in OLP in these two small groups of Iranian population was not confirmed with PCR method, but due to different ideas and reports in this field, proving or disproving of presence or etio¬logical role of EBV in OLP is continuously a question and needs to be examined in further studies.