Biological invasions of Erigeron annuus can impact the biodiversity of many ecosystems worldwide. It is capable of transforming native vegetation through high seed production, rapid growth, and strong ecological adaptability. This study provides detailed analysis of the distribution, phytocoenotic composition, and ecological niche of the species in Azerbaijan. E. annuus is found in a different of habitats from lowlands to mountain forests, according to field surveys carried out in the north-western, western, and southern parts of Azerbaijan between 2022 and 2024. The highest abundance and activity of E. annuus were recorded in the northwest of Azerbaijan (Balakan, Zagatala, Gakh districs), where the species dominated mainly in meadow and forest edge vegetation. Species distribution modelling (MaxEnt) achieved high predictive accuracy (AUC=0.95) and identified precipitation during the warmest quarter and annual precipitation as the main climatic factors determining the species’ distribution. Current suitability maps show that the humid districts of northwestern Azerbaijan are the most suitable habitats, while the lowland and arid districts are mainly unsuitable for the distribution of the species. Future projections (2081-2100) under the SSP1-2.6, SSP2-4.5 and SSP5-8.5 scenarios determined that the humid areas of the southern Greater Caucasus and Lankaran lowland, as well as the protected areas located here, mainly indicate persistently high suitability. These findings suggest that the current distribution areas of E. annuus will maintain stable populations and pose a long-term threat to native plant communities. Effective management strategies should therefore focus on early detection and control within these ecologically sensitive areas.