We experienced 3 cases of viral infections after lung transplantation. Case 1: Fifty-two-year-old male with pulmonary emphysema underwent left single lung transplantation from a cadaveric donor. Three months after transplantation he presented Epstein-Barr virus (EBV) viremia, resulting in multiple lymphadenopathy. Biopsy showed post-transplant lymphproliferative disorder, and he was treated successfully with rituximab. He is well without recurrence around 1 and a half years after treatment. Case 2: Thitry-eight-year-old male with pulmonary emphysema underwent double lung transplantation from a cadaveric donor. Four months after transplantation he showed multiple nodules in both lungs. Percutaneous biopsy showed post-transplant lymphproliferative disorder, and he was treated successfully with rituximab. He is well without recurrence more than 2 years after treatment. Case 3 : Twenty-four-year-old woman with lymphangioleiomyomatosis underwent living-related bilateral lobar lung transplantation. Three months after lung transplantation she presented cytomegalovirus viremia. Since it proved to be ganciclovir-resistant cytomegalovirus infection, she was treated with foscarnet successfully. She is well without recurrence about 2 and a half years after treatment.