Toxoplasma gondii infection reactivation predominantly occurs among patients after allogeneic haematopoietic stem cell transplantation. Mostly, reactivation occurs during first 3 months after transplant, especially when risk factors are present. We report a case of late cerebral toxoplasmosis reactivation, which was probably triggered by a brief course of corticosteroids, administered for chronic graft-versus-host disease (cGVHD). In the presence of risk factors, such as cGVHD, prophylactic treatment for toxoplasmosis should be reinstituted; Trimethoprim-sulfamethoxasole most probably prevented earlier reactivation of toxoplasmosis in our patient.