A 6-year-old patient with proven cutaneous lichen ruber showed reticular striae on the inner surface of the upper lip and hyperpigmentation of the attached gingiva. Oral lichen planus (OLP) is very rare in children, with a prevalence in adults of 0.5-2% of the general population and < 2-3% of the total being children. Because the patient was asymptomatic, no therapy was given, and regular follow-up was recommended. Although OLP is considered rare in children, clinicians should consider lichen planus as a possible differential diagnosis in the presence of a non-wipeable white lesion.