Abstract: A 56-year-old female patient presented with hair loss for 4 months. The topical characteristics of scale around the hair follicle was found under the dermoscope and other characteristics of pigtail-like curly hair and ingrown hair. Pathological examination showed epidermal atrophy, thinning, liquefaction and degeneration of basal cells, infiltration of lymphocytes in the superficial dermis, infiltration of lymphocytes around hair follicles, fibrosis around hair follicles. The diagnosis of lichen planus was made.

Key words: lichen planus, dermatoscope, pigtail-like hair, ingrown hair