Posttransplant lymphoproliferative disorder is a serious complication during a solid-organ transplant. A 28-year-old Asiatic man developed a cerebral lesion that was considered an abscess, while undergoing a kidney transplant. The lesion diameter did not go down with antibiotic therapy, so he underwent a complete surgical mass excision. Pathology showed a B-cell lymphoma. The Epstein-Barr virus-DNA by polymerase chain reaction in plasma was negative. He began chemotherapy with methotrexate and rituximab, and radiation therapy. He had to be restarted on regular hemodialysis 1 year after surgery. Three years after receiving the diagnosis, he was alive and had not developed any other posttransplant lymphoproliferative disorder. This report presents case of a patient who developed primary central nervous system B-cell lymphoma, 2 years after undergoing a kidney transplant. A combination of chemotherapy and radiotherapy is the best option for treatment of brain posttransplant lymphoproliferative disorder.