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Delusional parasitosis is characterized by the fixed belief that one is infested with parasites or small living creatures although there is no medical evidence for this. It can manifest itself as an isolated delusional disorder (primary), as a symptom of another psychiatric disorder or as an organic or toxic psychosis. Here, we describe a patient, who was diagnosed as having delusions of parasitosis that was successfully treated with risperidone. A 66-year-old female was presented with a 5-year history pruritus in her forehead and scalp. She believed that her hair had been infested with insects that bit her on the head. She was admitted to our clinic after having been treated by approximately 10 physicians. She underwent treatment for scabies, and treatment with antihistamines. None of these measures provided permanent relief. She reported being preoccupied by this symptom to the point of being able to think of nothing else throughout the day. The patient denied any other psychotic symptoms. Direct examination of the skin for bites, stings, or scabies were negative for parasites. On mental status examination, she was anxious and dysphoric. There was no evidence of cognitive decline. Results of the routine laboratory tests were in normal limits. Treatment with risperidone 2 mg daily was begun. Within 4 weeks she noted a decrease in her symptoms and the dose of risperidone was increased to 3 mg daily. She no longer felt as though she were being bitten. She remained asymptomatic on this dose of risperidone for 12 months. Antipsychotics both typical and atypical have been tried successfully to treat delusional parasitosis. In particular, has been recommended as a first-line treatment for this condition. However, despite the therapeutic efficacy of pimozide, the possibility of adverse effects, most notably extrapyramidal symptoms, has also been reported. The patient in the present case showed remission while receiving risperidone treatment. Although no controlled clinical studies are available, there are some case reports indicating the possible effectiveness of risperidone for delusional parasitosis. Based on the presented patient we believe that risperidone is an effective and well-tolerated agent for the therapy of delusional parasitosis. Therefore, risperidone should be considered as one of the possible treatment modalities for delusional parasitosis.