Human T-cell lymphotrophic virus (HTLV)-I/II infection has been considered a contra-indication to organ donation due to the risk of transmission of infection and the subsequent development of either adult T-cell leukemia or HTLV-I-associated myelopathy. However, neither the incidence of HTLV-I/II infection in organ donors nor the risk of transmission of HTLV-I/II by solid organ transplantation has been defined. Further, it is not known if HTLV infection contributes to significant morbidity in solid organ recipients. The purpose of this study was to evaluate the incidence of HTLV-I/II infection in organ donors in USA and to determine if transplanting these organs resulted in HTLV-related morbidity or mortality. We utilized the UNOS database to: (i) identify organ donors that were positive for HTLV-I or II infection between 1988 and 2000, and (ii) evaluate outcomes in the recipients of these organs. There were 25 HTLV-I/II-positive organ donors reported to UNOS between 1988 and 2000. Based on organ donors with a known HTLV-I/II status, the prevalence of HTLV-I infection in organ donors is 0.027% and the prevalence of HTLV-II is 0.064%. Twenty-two organs were transplanted from these HTLV-positive donors. There have been no reports of HTLV-I/II-related disease in the recipients with a median follow-up of 11.9 months. At our center, over the last 1.5 years there have been four multiorgan donors with false-positive HTLV-I/II screening assays, which resulted in the decision not to use organs from these donors. Based on the minimal chance of HTLV-related disease following transplantation of HTLV-I/II organs in this series, we recommend that careful consideration be given to transplanting organs from HTLV-I/II-positive organ donors.