Introduction: Febrile neutropenia, developing in hematological cancer patients, is a common complication requiring hospitalization and resulting in death. It is assumed that it is caused by infection until its reason is clarified. Hence, it requires a multidisciplinary approach and treatment as a medical emergency. For these patient groups, most of whom are at high risk, death caused by infection is attempted to be minimized by continuously updating treatment approaches. This study aimed to determine clinical characteristics, risk factors, distribution and frequency variance of isolated pathogens and impact in mortality of hematological cancer patients with febrile neutropenia prospectively.