In this double-blind clinical trial we compared the effect of clobetasol propionate ointment (Dermovate) in Orabase (50/50 v/v) and triamcinolone acetonide (Kenacort-T) in the treatment of erosive oral lichen planus (OLPe). All patients (n= 40) presented with uni-or bilateral atrophic or erosive lesions on the buccal mucosa or on the tongue. The ointments were applied during a 9-week period: the first 3 weeks twice a day, the following 3 weeks once a day, and during the final 3 weeks once every second day. After each 3-week period, the patients were asked to rate their symptoms on a visual analogue scale (VAS). In addition, the lesions were scored by a clinician using a four-point scale. Following treatment for 3 weeks, clobetasol propionate was found to be more effective than triamcinolone acetonide with respect to clinical improvement (P<0.05). No significant difference was observed following 6 and 9 weeks of treatment. Immunohistochemical analysis of biopsy specimens taken prior to and after the 9-week period revealed no change in the distribution of Langerhans cells irrespective of the treatment. The results demonstrate that clobetasol propionate compared with triamcinolone acetonide provides a more immediate clinical response in OLPe.