An 8-month-old male with X-linked lymphoproliferative disease underwent an unrelated, partially matched (with major mismatch at DR locus), cord blood stem cell transplant. Four months following the transplant, he developed immune thrombocytopenia with hemolytic anemia (Evans syndrome). He received multiple courses of intravenous immunoglobulin, anti-Rh D immunoglobulin, a pulse of high-dose corticosteroids and cyclosporine with some improvement of hemolytic anemia, but no improvement of the thrombocytopenia, Addition of vincristine, resulted in long-term resolution of thrombocytopenia and anemia, No major toxicity was observed during treatment. Vincristine should be considered as a treatment for refractory immune thrombocytopenia after hematopoietic stem cell transplantation.