OBJECTIVE: This study aims to compare the frequency of respiratory viruses using real-time and multiplex polymerase chain reaction technology and nasopharyngeal swabs taken during exacerbation of patients aged 0–18 years followed for febrile neutropenia (FN) with non-FN children. METHODS: This prospective study included a total of 40 patients with FN and malignancies followed at Eskisehir Osmangazi University, Department of Pediatric Hematology and Oncology. The control group (n=76) consisted of age-matched patients with upper respiratory tract infections (URTIs) or lower respiratory tract infections (LRTIs) who were admitted to the emergency service due to fever. RESULTS: Viral agents were detected in 16 of 53 FN attacks (30.1%). The most commonly isolated viruses were coronavirus (23.7%, n=9), influenza B (18.4%, n=7), and adenovirus (18.4%, n=7). Of 76 children diagnosed with URTI with fever (52.6%) had viral agents, and only 28 of them had a single agent. The most commonly isolated virus was adenovirus (28.6%, n=14). Viral factors were found in 32 of 42 patients (76.1%) patients diagnosed with LRTI, while respiratory syncytial virus was the most common virus in 27 patients (21.7%, n=5). CONCLUSION: Our study results show that viral agents play an important role in the etiology of FN. This is the first study to show that viral agents play an important role in the etiology of this disease and viral factors in non-neutropenic febrile children at the same time period by detecting respiratory viruses in 30% of FN cases. More similar studies provide antiviral therapy in selected patients, as well as these studies lead to reduce the use of antimicrobial agents or allow more selective use of antibiotics and/or the earlier discontinuation of these antibiotics in febrile neutropenic children who have been shown to have viral cause of respiratory tract infection based on clinical and microbiological/molecular diagnostic criteria.