Background: Seasonal H3N2 influenza virus, known for its rapid evolution, poses a serious threat to human health. This study focuses on analyzing the influenza virus trends in Jining City (2018-2023) and understanding the evolving nature of H3N2 strains. Methods: Data on influenza-like cases was gathered from Jining City’s sentinel hospitals: Jining First People’s Hospital and Rencheng Maternal and Child Health Hospital, using the Chinese Influenza Surveillance Information System. Over the period from 2018 to 2023, 7,844 throat swab specimens were assessed using real-time fluorescence quantitative PCR for influenza virus nucleic acid detection. For cases positive for seasonal H3N2 influenza virus, virus isolation was followed by whole genome s