Objective During the COVID-19 pandemic, the adopted containment measures have affected other respiratory virus epidemiology. Consequently, we aimed to describe the characteristics of respiratory virus infection in hospitalized pediatric acute respiratory infections (ARIs) patients prior to and throughout COVID-19 in East China.   Methods Nasopharyngeal secretions were collected from 9782 pediatric ARIs patients hospitalized in Shaoxing Maternal and Child Health Hospital from January 2018 to December 2022.  Changes in positivity viral detection rates and epidemiological as well as clinical characteristics were analyzed and compared. Results 1633 strains of 7 common respiratory viruses were detected, with a total positive rate of 16.37% (821/5021) in 2018-2019 and 17.06% (812/4761) in 2020-2022.  Compared with 2018-2019, RSV positive rate increased significantly in 2020-2022, while ADV, PIV-2, PIV-3, and flu-B detection rates were significantly reduced (P < 0.05).  The RSV-positive rate in winter increased significantly more than in other seasons (P < 0.05), while PIV-3 was mainly prevalent in spring and summer.   Conclusion During the COVID-19 pandemic, there were significant age distribution and seasonal differences in respiratory virus infection among hospitalized children with ARIs in East China.