Cyclosporin A(CsA) is an immunosupressive drug which inhibits predominantly T lymphocyte dependent immune responses. In recent years, CsA is reported to have significant steroid sparing effect in severe asthma. We used CsA top treat 12 steroid dependent asthmatic patients who had been on systemic steroids for an average of 8.5 years. During the baseline period lasting 3 months, therapy was standardized with inhaled beclamethasone, salbutamol and aminophylline and minimal necessary dose of steroid for each patient was determined. Treatment period lasted three months with 3 mg/kg/day CsA orally, the mean CsA whole blood level through the study was 77.25 ng/ml. In patients the daily dose of prednisone could be reduced from mean 31.43 mg to mean 8.57 mg (p < 0.01), while an average 34% improvement was observed in FEV1 values. However in one patient attempts to taper steroid doses were unsuccessful. Four patients were withdrawn from the study due to side effects of CsA. We suggest that CsA in steroid dependent severe asthma can reduce the requirement for systemic corticosteroids, however side effects of the drug must be weighed against its possible benefits.