Response to therapy of primary focal segmental glomerulosclerosis (FSGS) in adults is poor, most studies demonstrated no response at all. We report our experience from a retrospective study about 22 adults patients. All patients presented proteinuria at admission with a nephrotic syndrome in 86 percent of cases. A high blood pressure was noted in 25 percent. A response to corticosteroid was obtained in 8 patients (36%) with complete remission in 5 cases (23%). Three patients were corticosteroid-dependant, two out of them went in remission under cyclophosphamide in one case and under chlorambucil in the other case. Fourteen patients did not respond to corticosteroids. Eight received cyclophosphamide with partial remission in 4 cases and progression to chronic renal failure (CRF) in 4 cases. The six non-responders did not receive immunosuppressive drugs because of severe CRF in 4 cases. The mean duration of follow-up was 39 months (20-55). The response to corticosteroid of primary FSGS in adults remain low (30%). The use of cyclophosphamide has improved the global remission to 50 percent.