Background: Crimean-Congo hemorrhagic fever (CCHF) is one of the viral hemorrhagic fevers caused by tick bites. Common symptoms of the infection are fatigue, high fever, headache, and myalgia. In some patients hemorrhage may accompany these symptoms and is a sign of a poor prognosis. Typical laboratory changes are thrombocytopenia, leukopenia, elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine phosphokinase (CPK), and lactate dehydrogenase (LDH), and prolongation of prothrombin time (PT) and activated partial thromboplastin time (aPTT). Mortality rates vary between 3% and 30%. The aim of this study was to determine the factors affecting the prognosis of CCHF.