Crimean- Congo Hemorrhagic Fever (CCHF) is a viral zoonotic tick-born disease with a mortality rate of up to 50% in humans. After a short incubation period, the disease is characterized by sudden fever, chills, severe headache, dizziness, back, and abdominal pain. Additional symptoms can include nausea, vomiting, diarrhea, neuropsychiatric, and cardiovascular changes. In severe cases, hemorrhagic manifestations, ranging from petechiae to large areas of ecchymosis develop. The CCHF Virus (CCHFV) is from the genus Nairovirus and family Bunyaviridae. CCHFV is transmitted to humans by the bite of infected tick and by direct contact with blood or tissue from infected humans and livestock. In addition to zoonotic transmission, CCHFV can be spread from person to person and is one of the rare hemorrhagic fever viruses able to cause nosocomial outbreaks in hospitals. CCHF is a public health problem in many regions of the world e.g Eastern Europe, Asia, Middle East, and Africa. The history of CCHF in Iran shows that the disease has been detected in Iran since 1970. From 1970 to 1978 some scientists worked on serology and epidemiology of this disease in humans and livestock in Iran. Since 1999 , establishment of a surveillance and laboratory detection system on viral hemorrhagic fevers particularly on CCHF has had benefits. One of which is the fact that a mortality rate approaching 20% in the year 2000 remarkably dropped to 6% in the year 2007.