This mechanism study examines the role of quercetin at inhibiting influenza infection. Influenza A viruses (IAVs) are responsible for seasonal global pandemics and mortality, and genetic variations make it almost impossible to develop timely vaccines. Novel therapeutic strategies are anti-influenza agents are therefore of great interest. Two classes of anti-influenza drugs are widely used to inhibit viral entry and development, with varying side effects reported. Targeting viral entry and suppression of the infection at its early stage is an attractive therapeutic strategy. Quercetin is known to have anti-viral effects, alongside antioxidant, antibacterial and antiproliferation properties. Cells were infected with different influenza strains and exposed to quercetin, and the cytopathic effect and inhibition rates were measured at intervals. The results showed quercetin reduced transcription in influenza-virus-infected cells in a dose-dependent manner. This implies that quercetin’s mechanism of action may inhibit influenza in the early stage of viral attachment. Additional experiments found that quercetin directly targets the viral hemagglutinin protein particles rather than the host cells. The study concludes that quercetin possesses interesting anti-influenza activities which could be developed as a future therapeutic option for the therapy and prophylaxis of IAV infection.