The authors report on the first coming out in Gabon of human monkey-pox. Four children in the same family were simultaneously attacked. In one of the two fatal cases, diagnosis of monkey-pox was confirmed by the isolation of the virus. In the three other cases, diagnosis was based on clinical and epidemiological findings. The coming out of monkey-pox in Gabon squares with sporadic coming out of this zoonosis observed in the humid tropical forests of west and Central Africa. Two fatal cases presented some symptoms of hemorrhagic fever and cutaneous symptoms did not dominate the clinical feature. As a consequence of it, monkey-pox has to be envisaged in similar cases. The attack of liver and spleen in man has not been documented up till now, as it has been for monkeys. Classical diagnosis is based on the isolation of the virus from a cutaneous lesion. In the present case, the virus was isolated from a blood sample. Epidemiological study did not reveal any interhuman transmission evidence, nor the source of infection.