Introduction. Plant pollen causes various allergic reactions in humans, including respiratory diseases, immune system disorders, bronchitis, conjunctivitis, dermatitis, and hay fever. These diseases affect up to 30% of the world's population. In large cities, trees and shrubs used in landscaping are significant sources of allergenic dust. Despite this, the greening of cities worldwide often occurs without considering the allergenic properties of plants. With the development of proteomics, it has become possible to assess the degree of allergenicity of proteins that make up plant pollen in detail. Based on this information, a scale of potential allergenicity for woody plants has been developed. The aim of this study is to assess the allergenic potential of woody plants in the urban flora of Rostov-on-Don.Materials and Methods. The object of the study was trees and shrubs used in the landscaping of Rostov-on-Don. The analysis of floristic data was based on the materials obtained during field work in 2023 on the territory of Rostov-on-Don. The author also used the lists of the city's dendroflora compiled between 2007 and 2022. The assessment of the potential allergenicity of woody plant species was conducted on a five-point scale, with 0 indicating plants that did not pose an allergic hazard, 1 indicating a low allergenicity level, 2 indicating a medium class, 3 indicating a high level, and 4 indicating a very high level of allergenicity.Results. In the flora of woody plants in Rostov-on-Don, 61 species of potentially allergenic plants were identified, posing varying levels of danger to human health. The share of all types of potentially allergenic woody plants was 30% of the total number of urban woody flora species in the city. The most powerful sources of allergenic pollen included nine species (Fraxinus Excelsior, Betula Pendula, B. Verrucosa, Platycladus Orientalis, etc.), which posed the greatest threat of hay fever and other allergic reactions. As a rule, these were typically wind-pollinated plants that produced maximum amounts of pollen. The list of potentially allergenic species included a significant number of adventitious species (24 species), which made it difficult to control their spread. A taxonomic analysis of potentially allergenic species was carried out at the order level, for which specific protein reactions were identified and detailed approaches to the prevention and treatment of hay fever were developed. The orders Pinales and Fagales form the bulk of allergenic pollen in the winter-spring period.Discussion and Conclusion. For the first time, studies were conducted on the allergenic activity of urban woody flora in the southern regions of Russia. An assessment of their allergenic potential allowed us to determine the level of threat of allergic reactions in humans. The greatest danger comes from both allergenic and invasive species that can spread actively and increase in numbers. Representatives of the Pinales and Fagales orders have proven to be significant sources of allergenic pollen, as they often have high ornamental qualities and play a prominent role in design projects. In some cases, it may be possible to replace these cultures with less allergenic alternatives, such as representatives of the Rosales order, to reduce the risk of allergic reactions.