Since 2015, the French poultry production has been threatened almost every year by a reintroduction of the highly pathogenic avian influenza (HPAI) H5 viruses. In the 2021-2022 season, the number of poultry outbreaks in France accounted for half of the total number of outbreaks in Europe. After four epizootic waves, HPAI viruses seem to stay endemic in the European wild bird population and represent a continuous threat to the French poultry production. These events have mainly affected fattened duck farms but also turkey, layer and broiler farms. If some risk assessment studies have been conducted on French duck farms, no work has been done on broiler and layer farms. Due to the broilers production process (all-in/all-out production system), broilers are often considered less exposed to the risk of avian influenza virus spread than other productions even if the broiler sector is the main poultry sector in France. Layers have the longest life span of any poultry production, which is often considered a higher risk for disease introduction. The objective of this work was to assess the risk of transmission of avian influenza (AI) virus from a farm to another within the French broiler and layer production networks. This study used the OIE risk assessment framework. We structured the French broiler and layer production networks using respectively eight and seven different types of farms (the combinations of selection/production, indoor/free-range, integrated/independent) which were considered according to their biosecurity level. We assessed the transmission risk through eight different pathways focusing on indirect contacts: human in direct contact with birds, chick transport, bird collection, feed delivery, manure management, dead bird management, shared material and egg management. After developing a tree of farm-to-farm transmission scenarios for each transmission route, data were collected through literature review or expert elicitation. Two separate questionnaires w