Virus reproduction and the time course of changes in liver and kidney functions and in the blood clotting system were studied in the visceral organs of green monkeys and baboons infected with Ebola virus (subtype Zaire). It was shown that monocytes and macrophages were the first cells to be infected with the virus, followed by hepatocytes, adrenocorticocytes, fibroblasts, and endotheliocytes. The early and late pathologic changes in the monkey organs are described. Biochemical data on changes in blood clotting and liver and kidney functions in the course of the infection are presented. The responses of blood clotting and vascular permeability were species specific: Fibrin deposited in blood vessels in green monkeys, while hemorrhages developed in baboons. The results show that species-specific features of monkeys must be taken into account when choosing an experimental model for studying Ebola virus infection.