Children with cancer became a major high-risk group during the COVID-19 pandemic. It has become difficult for patients to reach practical and safe care and treatment all over the world. The late diagnosis of many childhood cancers was driven by limited access to healthcare due to the pandemic and fears of COVID-19 that prevented parents from making an early medical assessment of their child's symptoms. Acute respiratory diseases are an important cause of morbidity and mortality in children with cancer, regardless of the COVID-19 pandemic and were seen less frequently in the pandemic during the lockdown and distant education period in comparison to the time before the pandemic in children with cancer. Acute respiratory viral infections frequently cause febrile neutropenia attacks in children under five years of age. A three year retrospective cross-sectional study was performed in a tertiary care university hospital. Children with cancer who presented to the Department of Pediatric Hematology and Oncology with the diagnosis of acute respiratory viral infection were included in the study if they had available results of multiplex polymerase chain reaction (PCR) of nasopharyngeal aspirate samples. The qualitative detection of 18 respiratory viruses and four bacterias were detected by the real-time multiplex polymerase chain reaction. Sixty-six patients with 93 acute respiratory viral infection were included in this study. Seventy of 93 (75%) samples were positive for at least one pathogen. The most common three viruses were HRV, Influenza H1N1, and Influenza H1N3, respectively. Other than COVID-19, the risk of severe acute respiratory viral infections are always important in children with cancer and during the pandemic, hygiene measures and social restrictions caused a reduction in the number of acute respiratory viral infection. This study is critical because it shows the distribution of agents in children with cancer who had acute viral upper respiratory tract infections in the near term before the pandemic.