Background: Lichen planus (LP) is a chronic mucocutaneous disease of uncertain etiology. Recent reports suggest that LP is an extrahepatic manifestation of Hepatitis C infection.Objective: To determine the association of Hepatitis C virus (HCV) infection with oral LP and to study the tests of liver function in patients with oral LP.Study Design: A cross-sectional case-control study was carried out on 25 patients with oral LP and an equal number of controls. The study was conducted in the outpatient department of a dental college for a period of six months between January and June 2008. The sera of the patients and controls were tested for HCV ribonucleic acid (RNA) using reverse transcription primed-polymerase chain reaction and liver function tests (bilirubin, transaminases, and alkaline phosphatase).Results: Of the 25 patients with LP, three (12%) had HCV infection. None of the controls had HCV RNA positivity (P = 0.2347). Oral LP patients had higher serum bilirubin and transaminases when compared with controls (P < 0.05). However, there was no significant difference in alkaline phosphatase. HCV-positive and -negative patients did not differ significantly in liver function tests.Conclusions: An increased prevalence of HCV infection was seen in oral LP patients. Our findings support a possible etiological association between these two diseases