This survey is applied on the brain of the Rat using Computerized Tomo-graphy (CT) and Latex neoprene injection technique to recognize brain problems and provide anatomical data. Eight carcasses of rats, the specimens were carried out from local markets to the Department of anatomy in veterinary medicine, Cairo University. The brain of three carcasses were separated from the whole body for morphology, three specimens were injected with latex to observe the distribution of arterial blood supply and two others for C.T. The brain of rat measured about 2 cm long, 0.75 cm width in the widest part and about 6 gm. weight. Anatomically it could be divided into cerebrum, cerebellum and brainstem. The main blood supply of the brain is the internal carotid arteries and the basilar artery. The communication of the internal carotid and the basilar arteries formed a network of anasto-mosing vessels, polygonal shape-like arterial anastomosis, rostrally and caudally closed which known as circle of Willis and placed at the base of brain where it surrounded the optic quiasm and the tuber cinereum.