Post-transplant lymphoproliferative disorder (PTLD) is one of the most important complications of solid organ transplantation or hematopoietic stem cell transplantation. Most PTLDs are associated with Epstein-Barr virus (EBV) infection. Although post-transplant Hodgkin lymphoma (HL) is included in PTLD, there have been no studies in the literature on adult cases of post-transplant HL after cord blood stem cell transplantation (CBSCT). This is due to the fact that EBV infection of cord blood cells usually does not occur, and EBV-infected lymphocytes of the recipient should be eradicated by preconditioning therapy. We report a 26-year-old woman case of post-transplant HL, which occurred after CBSCT for relapsed acute lymphoblastic leukemia. Three years and eight months after CBSCT, the enlarged cervical lymph node was histologically diagnosed as EBV associated post-transplant HL, which showed immunophenotypes of classical HL and latency type II EBV infection. She underwent chemotherapy, and has survived 4 years and 6 months after CBSCT. Differential diagnosis of post-transplant HL with good prognosis and HL-like PTLD with aggressive behavior is important, and immunohistochemical methods were useful and essential for it. The source of EBV associated HL in this case will be discussed. [J Clin Exp Hematopathol 49(1) : 45-51, 2009]