This book is intended to elucidate the topography, morphological features, musculature, and the arterial blood supply of cloaca in ostrich in order to provide understanding for veterinarians who deal with such recently distributed bird in Egypt and other countries that play an important economic role in meat, skin and feather production. This work was carried-out on cloacal specimens of mature, immature male and immature female ostriches (Struthio camelus). The cavity of the cloaca is delimited cranially from the colonic pouch of the terminal colon by unique strong annular colocoprodeal fold. The phallus of the ostrich is formed of paired phallic bodies, phallic sulcus, elastic vascular body and phallic muscles. The cloaca of ostrich had two sets of cloacal muscles; extrinsic and intrinsic muscles. The arterial blood supply of the cloaca and its associated cloacal muscles are originated mainly from the internal pudendal artery and in-part from the caudal mesentric and external pudendal arteries.