The impact of ungulates on the forest vegetation has far-reaching consequences: it decreases species diversity and the production of biomass, causes soil dehydration, erosion and eutrophication the entire forest community. The article addresses the influence of fallow deer and mouflon on the forest vegetation in the Holedná game reserve (western border of the city of Brno, South Moravia, Czech Republic) and compares differences with the forests adjacent to the game reserve. Sixty localities were distributed randomly and phytosociological relevés subsequently recorded there according to the age of the stands inside and outside of the game reserve. The differences in floristic composition were compared for trees, shrubs and herbs, the herb layer species number, the diversity indices and the values of Ellenberg indicators. In the game reserve, a significant difference was found in the coverage of the herb and shrub layer, which was significantly lower than outside the territory. Furthermore, the increased amount of nitrophilous, heliophytes and ruderal herb species inside the game reserve exhibited affiliation to the interior of game reserve. Besides, young trees and woody sapling were less abundant or even missing inside of game reserve. By contrast, the frequency of typical species of oak-hornbeam forests was higher outside game reserve. Due to the higher number of animals and consequent disturbances, nitrophilous plant species dominate in the herb layer of the game reserve, while forest species are more often represented outside it.