The paper highlights the impact of two cross-border poultry infections with zoonotic potential (avian flu and Newcastle disease) on the functioning of industrial poultry farms in the former Soviet Union counties (Ukraine, Russia, Belarus, Kazakhstan), where the poultry industry is fairly well-developed. Despite the permanent vaccination of poultry against Newcastle disease in industrial poultry farming, the disease still affects individual farms in Ukraine, the Russian Federation, and Kazakhstan. In case of outbreaks, the Russian Federation and Kazakhstan use inactivated influenza vaccines. In Ukraine, for almost 20 years, outbreaks of influenza have been confirmed mainly on individual farms, and one outbreak of highly pathogenic influenza was reported on an industrial poultry farm in 2020. In the Russian Federation, highly pathogenic influenza occurs on industrial poultry farms more often. In Russia, seven industrial poultry enterprises were affected by influenza in 2016-2017, and eight in 2018. Infection of poultry with influenza virus on poultry factory farms is an indication of shortcomings in compliance with biosecurity measures. Influenza and Newcastle disease are always likely to occur in the countries in question, as wild birds migrate through their territory, and they are a reservoir of pathogens, therefore outbreaks are often associated with spring and autumn migrations of wild birds. In all of said countries, a large number of poultry is kept by individual households, where basic biosecurity, sanitation and preventive vaccination measures are not applied. This component is often crucial in bringing viral infections such as influenza and Newcastle disease on large poultry farms. As a result, the virus is brought onto poultry farms by synanthropic birds, humans, transport, feed, etc.