The Arabian Oryx (Oryx leucoryx) is a wild animal that is distributed in the gulf countries and elsewhere. Ultrastructural illustration of normal blood cells of the Arabian Oryx is vital because it provides a basis of relating structure to function and is fundamental to be able to compare the normal physiological state to that of a pathological state. Since intensive ultrastructure demonstration of the normal blood of Arabian Oryx (Oryx leucoryx) is lacking in the literature, this investigation will be considered as a fundamental base line of normal cyto-morphological evaluation of blood tissues. The aim of this present study is to examine the ultrastructure morphology of blood cells of Oryx and compare it with other mammalian species. Blood samples from 20 apparently healthy Arabian Oryx were processed for the transmission electron microscope. Four types of leukocytes, lymphocytes, monocytes, neutrophils and eosinophils and thrombocyte were identified. Unique to the platelets for this species was the presence of multivesicular bodies which have previously only been described in cultured megakaryocytes of human platelets but not in other animal species. Pseudopodia containing microtubules are also a unique characteristic of the platelets of the Arabian Oryx as well as the lack of an Open Canilicular system. Similar to humans, the medium-sized lymphocytes commonly exhibited multi-vesicular bodies, a granular not described in the lymphocytes of other animal species. Monocytes have both multivesicular bodies, as well as granules with halos are considered unique features of the monocytes of the Arabian Oryx. Small sizes, presence of the nucleolus and the large size of mitochondria are distinctive features of the neutrophils of the Arabian Oryx. Multivesicular bodies are also found in the neutrophils of the Arabian Oryx. Crystalloid granules as well as microgranules are considered as markers for the Arabian Oryx eosinophils.