A mathematical model has been developed to simulate the time average blood flow throughout the circulatory system of the human body. It was assumed that whole blood obeyed Cassons equation and the flow properties were calculated by means of this relationship. The model is a complete computer simulation designed to calculate the steady flow rates, average pressure gradients, and mean hemoglobin flow rates over the entire vascular system. Pertinent shear stress and shear rate data were submitted to the model to determine the extent to which the above properties were affected by the disease, sickle cell anemia. Possible extension of the model for evaluation of proposed theraputics for sickle cell anemia are discussed.