In contrast to the abundant information available on neoplasm in human and domestic animals, little information is available on neoplasm of captive wild animals. Most tumor studies for wildlife had been restricted to a single species or single tumor. A large scale of wildlife tumors has not been studied much yet. The objectives of the investigation were to establish database for wildlife neoplasm and provide references for wildlife medicine and a model for comparative oncology. In this study, all tumor cases of mammals, birds, and reptiles died at Taipei Zoo from years 1994 through 2003 have been collected. Routine histopathology and immunohistochemistry were employed to study tumor classification. Additional data of species, sex, age, site and type of tumors were analyzed together. A total of 2,657 necropsied cases, including 1,335 mammals, 873 birds and 449 reptiles were obtained. One hundred and sixty-three tumors of various types were diagnosed in 150 captive wild animals; and detected in mammals, birds and reptiles at rates of 8.1 % (108/1,335), 4.2 % (37/873) and 1.1 % (5/449), respectively. The neoplasms most frequently found among mammals originated from skin and soft tissue (22.0 %, 26/119), next was hepatic tissue (17.0 %, 20/119) and followed by hemolymphatic system (13.4 %, 16/119). Skin and soft tissue tumors were most frequent mammalian neoplasm and similar to the neoplasia found in the domestic animals. The most prevalent avian neoplasm was lymphosarcoma (33.3 %, 13/39). The relatively high incidence of avian neoplasm of lymphosarcoma suggests possible causes of the avian leucosis virus and Marek’s disease virus. Five individual neoplasms occurred in different reptilian species. The prevalence of malignant tumors was 64.0 % greater than that of the benign tumors 36.2 %. These results suggest that most wild animals may die from malignant tumors associated with cachexia and organ dysfunction. Causes and risk factors of wild animal neoplasma remain undetermined.