Psychiatric classificatory systems consider obsessions and compulsions as forms of anxiety disorder. However, the neurology of diseases associated with obsessive–compulsive symptoms suggests the involvement of fronto–striatal regions likely to be involved in the mediation of the emotion of disgust, suggesting that dysfunctions of disgust should be considered alongside anxiety in the pathogenesis of obsessive–compulsive behaviours. We therefore tested recognition of facial expressions of basic emotions (including disgust) by groups of participants with obsessive–compulsive disorder (OCD) and with Gilles de la Tourette's syndrome (GTS) with and without co–present obsessive–compulsive behaviours (GTS with OCB; GTS without OCB). A group of people suffering from panic disorder and generalized anxiety were also included in the study. Both groups with obsessive–compulsive symptoms (OCD; GTS with OCB) showed impaired recognition of facial expressions of disgust. Such problems were not evident in participants with panic disorder and generalized anxiety, or for participants with GTS without obsessions or compulsions, indicating that the deficit is closely related to the presence of obsessive–compulsive symptoms. Participants with OCD were able to assign words to emotion categories without difficulty, showing that their problem with disgust is linked to a failure to recognize this emotion in others and not a comprehension or response criterion effect. Impaired recognition of disgust is consistent with the neurology of OCD and with the idea that abnormal experience of disgust may be involved in the genesis of obsessions and compulsions.