The effect of cognitive therapy (CT) on resistant burning mouth syndrome (BMS) was studied. Thirty patients with resistant BMS after odontological and medical treatment were randomly divided into two equal groups; a therapy group (TG) was treated with CT and an attention/placebo group (APG) served as a control group. The intensity of BMS, which was estimated by the use of a visual analogue scale, was significantly reduced in the TG directly after CT was completed and was further reduced in a 6-month follow-up. The APG did not show any decrease in intensity of BMS. The results of this study indicate that, in some cases, resistant BMS probably is of psychological origin.