We investigated a male, aged 4 years 11 months, who fulfilled the criteria of Asperger syndrome). In addition to the typical pattern of autistic symptoms, psychological testing revealed prosopagnosia in tasks for face recognition and matching. Prosopagnosia was also present when he tried to identify the faces of his parents and himself in photographs whenever these were presented with photographs of other persons. Although impairment in reciprocal social interaction in individuals with Asperger syndrome is closely correlated to their impaired perceptional abilities in non-verbal communication, especially facial expression, overt prosopagnosia seems to be a rare neuropsychological symptom in persons with autistic disorders.