Lichen planus is rare in Korea. and oral lichen planus is even rarer. To our knowledge, this is the first case reporting in Korean dermatological literature. 57 year-old man was seen for erythema with white striation on the oral mucosa in December 1981. The initial lisior s appeared on the buccal mucosa of left side of oral cavity 10 months ago. Thereafter he noticed similar lesions on the right side of buccal mucosa, hard palate, left side of upper and lower gingiva and left side of the lower lip. Histopathological and direct immunofluorescence studies showed typical features of lichen planus. Administration of griseofulvin(0. 5gm. of Fulvicin' daily) for 4 weeks resulted in no clinical improvement. Oral retinoid(25mg of Ro 10-9359 daily) for 11 weeks resulte3 in healing of lesions with no side effect except slight dryness of the mouth.