Oral lichen planus (OLP) is a chronic infl ammatory disorder that aff ects the oral mucous membrane. Th e prevalence of OLP in the population is considered to be 1%-2% (1). Th e etiology of OLP is not known. Th e immune system very probably plays the primary role in the development of this disease. During the last decades, several studies have suggested that human papillomaviruses (HPVs) are involved in the development of premalignant and malignant lesions (2). Th e causal role of HPV has been reported for OLP and oral squamous cell carcinoma, but there are wide variations in disease prevalence with regard to diff erent geographic populations (3). Th e aim of this study was to determine the prevalence of HPV on the mucosa in patients with OLP and compare it with healthy mucosa.Study protocol has been approved by the local ethical committee. Written informed consent was obtained from all subjects entering the study. Patients with OLP were included based upon following criteria: clinically diagnosed OLP according to objective examination (single physician) and histologically confi rmed OLP. OLP was classifi ed according to criteria previously published by World health Organization and modifi ed by van der Meij et al. (4). Smokers and patients with alcohol abuse history were excluded from the study. Sex-and age-matched controls were chosen from individuals undergoing various dental procedures with no known mucosal disease. Native tissue samples were sent for HPV genome detection. HPV DNA was extracted from native tissue. All samples were screened for the presence of HPV DNA by PCR amplifi cation with primers GP5+/ GP6+ located within the HPV L1 gene. Th e sequences of the forward and reverse primers used were FW (GP5+): 5'-TTTGTTACTGTGGTAGATACTAC-3' and REV (GP6+): 5'-AAAAATAAACTGTAAATCATATT-3'. Th is allows the detection of 37 HPV types, specifi cally 6,11,16, 18, 26, 31, 33, 35, 39, 40, 42, 45, 51, 52, 53, 54, 55, 56, 58, 59, 61, 62, 64, 66, 67, 68, 69, 70, 71, 72, 73 (MM9), 81, 82 (MM4), 83 (MM7), 84 (MM8), IS39, and CP6108. HPV typing was performed, however, due to low amounts of DNA it was not possible to analyze the results. Chi-square and Student t-test were used for comparisons. P value <0.05 was considered statistically signifi cant. A total of 45 patients with confi rmed diagnosis of OLP were examined for HPV, of whom, 33 (73.3%) were woman and 12 (26.7%) were men. Th e mean age of the patients was 56 years (±14.96) with an overall range of 33-77 years. Th e control group consisted of 24 individuals, 19 (79.2%) were women and 5 (20.8%) were men. Th e mean age of the individuals in control group was 56.1 years (±11.41) with an overall range of 29-81 years. Th ere was no statistical signifi cance according to age (p = 0.96) and gender (p = 0.59) between OLP patients and controls. Th ere were 24 (53.3%) HPV-positive patients with OLP and 21 (46.7%) patients were HPV-negative. In the control group there were 12 sub-