T-cell large granular lymphocytic (T-LGL) leukemia is a rare clonal proliferation presenting with cytopenia, splenomegaly, and autoimmune manifestations. It has rarely been described in recipients of solid organ transplants. We report the clinical case of a young kidney transplant recipient that developed T-LGL leukemia 3 years after kidney transplantation. The disorder manifested with a severe form of autoimmune hemolytic anemia in the absence of other laboratory abnormalities. The anemia was successfully treated with an intense course of corticosteroids ands witch of immunosuppressive therapy from a calcineurin inhibitor to sirolimus, a mammalian target of rapamycin inhibitor. Our case shows that autoimmune hemolytic anemia can be a life-threatening manifestation of T-LGL disease. The antiproliferative effects of sirolimus may be useful in the treatment of symptoms of T-LGL leukemia in kidney transplantation.