Adaptation of the Crimean-Congo hemorrhagic fever (CCHF) virus to continuous culturing in Vero-E6 cells was studied by coculturing of infected and intact cells. Adapted strain Hoja-A exerted a complete cytocidal effect and was characterized by a high level of virus accumulation in the early period of the infection. The resultant strain survived through more than 80 passages and retained the newly acquired properties; lyophilized, it can be stored for a long time. Availability of such a strain opens new vistas in studies of the CCHF agent.