The H9N2 subtype of influenza virus is endemic in various regions of Iran and has the ability to be transmitted from birds to humans, which makes it a potential candidate for future pandemics. Given the increasing interest among different segments of Iranian society in commercial poultry farming, the need for further research to increase understanding of the virus characteristics, pathogenesis, and associated risks to humans is clearly felt. This study evaluated the duration of infectivity of H9N2 influenza virus for humans in contact with infected chickens and determined the period of virus shedding from infected birds. In this study, allantoic fluid containing 10^6 EID50/ml of H9N2 influenza virus was intranasally inoculated into Ross chickens. Samples from the throat and feces of the birds were collected at different days after inoculation, and the presence of influenza virus was assessed using RT-PCR. This study showed that after infection, shedding of influenza virus from the throat and feces of birds can begin two days after infection and continue until days 10 and 17 after contact, and then spread to the surrounding environment. The findings suggest that the endemic Iranian H9N2 subtype can be shed from the throat and feces of commercial poultry and contribute to the environmental spread of the virus. The greatest risk from infected commercial poultry to humans occurs between days 2 and 5 after infection. Given the zoonotic nature of the influenza virus and the proximity of laying hen farms to urban areas, it is essential to increase public awareness about this disease, the modes of viral transmission, the duration of shedding, the potential risks to human health, and control and prevention strategies.