Fever is a common presenting complaint among adult or pediatric patients in the emergency department setting. Although fever in healthy individuals does not necessarily indicate severe illness, fever in patients with neutropenia may herald a life-threatening infection. Therefore, prompt recognition of patients with neutropenic fever is imperative. Serious bacterial illness is a significant cause of morbidity and mortality for neutropenic patients. Neutropenic fever should trigger the initiation of a rapid work-up and the administration of empiric systemic antibiotic therapy to attenuate or avoid the progression along the spectrum of sepsis, severe sepsis, septic shock syndrome, and death.