Many reports show evidence of the disruption of central noradrenergic activity in the etiology of schizophrenia. A few studies show positive effects of a specific alpha(2)-agonist, clonidine, on cognition and on positive and negative symptoms of schizophrenia. In this report, we tried clonidine for the treatment of auditory hallucinations in a patient with schizophrenia who had low compliance with antipsychotic treatment. At the end of seven days, auditory hallucinations decreased dramatically. Moreover, almost all auditory hallucinations disappeared at 6-months follow-up. This is the first case report showing the efficacy of clonidine monotherapy on auditory hallucinations in schizophrenia. However, the mechanism of action of clonidine remains hypothetical. The dramatic improvement observed in this case in the absence of any adverse effects suggests that controlled trials of the effect of clonidine on auditory hallucinations may be of clinical importance.