Urban green spaces provide a variety of habitats essential for maintaining biodiversity in cities, including epiphytic fruticose lichens. However, urban environments differ considerably from rural and natural areas, which are less affected by human activities. This study investigated the occurrence and ecological determinants of epiphytic fruticose lichens in the city of Brno (Czech Republic), where this ecologically sensitive group of lichens had not been previously examined. Field surveys were conducted at 30 localities representing forests, parks, and orchards, where a total of 240 trees were examined for the presence of epiphytic fruticose lichens. For each tree, data on species identity, canopy openness, trunk circumference, herbaceous cover, dead wood, distance from the city center, and land use were recorded to assess which factors influence the occurrence and diversity of epiphytic fruticose lichens. A total of 177 epiphytic fruticose lichen thalli of six species were found in Brno. Of the variables considered, the occurrence of epiphytic fruticose lichens was primarily associated with tree species composition. All epiphytic fruticose lichen species were found on deciduous trees, particularly fruit trees, with the highest frequency in orchards. The effects of light availability and tree trunk circumference were also significant. These findings highlight the importance of urban orchards and other green spaces with diverse fruit trees for sustaining urban lichen diversity. The preservation and proper management of such habitats are therefore essential for maintaining and supporting populations of sensitive epiphytic lichens within cities like Brno. Keywords: City conditions · Ecological indicators · Tree species diversity · Urban green spaces.