We report a case of 13 years old male patient. He was diagnosed as glycogen storage disease Ib at 6 month age, and received cadaver donor liver transplantation at 2 years and 4 months. He underwent immunosuppression for 9 years with several im-munosuppressants including tacrolimus. Then he visited hospital for gum swelling and showed multiple malignancy suspicious lesions at nasal cavity, maxilla, mandibula, fron-tal bone, temporal bone, C1 and C2 spines, and several submandibular lymph nodes at radiologic study. Biopsy was done at oral cavity lesion, and histologically diagnosed as diffuse large B-cell lymphoma. The tissue specimen showed positivity in Epstein-Barr virus polymerase chain reaction (PCR). After diagnosis, the patient stopped all im-munosuppressive agents and received 9 cycles of CHOP (cyclophosphamide, adriamy-cin, vincristine and prenisolone) chemotherapy for 8 months, then the patient achieved radiologic remission state, and being well without any signs of recurrence for two years of follow up.