Background: The clinical presentation of lichen planus varies depending on the area involved. It occurs in less than 1% of the world’s population: also, the prevalence in Korea is relatively low. However, the number of our outpatients has been increasing rapidly. Objective: We studied the clinical characteristics of 100 patients with biopsy proven lichen planus. Methods: We reviewed the medical records and clinical photographs of 100 patients who had been diagnosed with lichen planus during the last 10 years, from January 2002 to December 2011. Results: Over the past 10 years, patients with Lichen Planus accounted for 0.196% among the new outpatients of this dermatology. The rate of Lichen Planus increased when it occurred on the skin, except for the Mucosal area. Of the 100 outpatients, 62% were men and 38% were women. The mean age at diagnosis was 54 years, and more than half of the patients were between 40 and 60 years of age. The most common site of lichen planus was the lip,which was found in 44% of the patients. Oral lesions were the second most commonly involved site at 28%,followed by the body at 20% and the genital area at 8%. The patients complained of various symptoms such as pain, burning sensation, pruritus, and irritation. Various treatments had been tried by all patients. Conclusion: This study of domestic patients with Lichen Planus is the biggest clinical research performed at a single center. The clinical features of patients in this survey share many similarities with those reported previously,but showed some differences too.