Tardive dyskinesia (TD) is a long-term severe complication of antipsychotic treatment, with mean prevalence of 20-35%. The aim of this study was to evaluate effects of clozapine in severe TD. In an open trial seven patients with schizophrenia and severe TD were given clozapine for 6 months. Tardive dyskinesia severity was evaluated with AIMS and ESRS and schizophrenic psychopathology with PANSS. Clozapine mean dose at the end of the study was 392.86 mg/day. A mean reduction of 52% was observed in ESRS scores for TD. Two patients also had dystonic movements, and there was 50% reduction in one of them and complete remission in the other. There was also a 27% mean reduction in PANSS scores. Clozapine seems to be an alternative in the treatment of schizophrenic patients with severe TD.