Only one virus, Avipox, has been documented in wild birds in Hawaii. Here, using immunohistochemistry and PCR, we found that two native threatened Hawaiian geese, one with multicentric histiocytoma and another with toxoplasmosis and one Laysan albatross with avian pox were infected with reticuloendotheliosis virus (REV). The virus was isolated from one of the geese by cell culture. PCR surveys of other Hawaiian geese with various pathologies, avian pox cases, and pox viral isolates failed to reveal REV suggesting the virus is uncommon, at least in samples examined. The full genome of the Gag, Pol, and Env genes were sequenced for all three infected birds and revealed geographic divergence of the Pol gene suggesting it to be under strong selective pressure. Our finding of REV in Hawaii makes this only the second virus documented in native Hawaiian birds associated with pathology. Moreover, the presence of REV in a pelagic seabird is unusual. Future surveys should seek the reservoir of the virus in efforts to trace its origins.