Alien woody species are one of the most succesful invaders in the world, despite of 35 these species are frequently used for afforestations in several regions such as semi-arid lands. 36 Shrubs and trees can form important patches, creating microhabitats in the open area of arid 37 lands. These vegetations have unique species composition and coexistence of species modes. 38 However, effects of solitary conifer species on the understory vegetation are lacking. This study 39 evaluated the effects of the solitary native and invasive conifer species, Juniperus communis 40 and Pinus nigra on the beta diversity of the surrounding vegetations. To determine the impacts 41 of the conifer invasion on species richness and structure in this habitat, a field study was 42 conducted in Pannonic dry sand grassland in the growing season of 2018. The presence of plant 43 and lichen species were recorded in the vegetation around each six selected solitary conifers. 44 26 m long circular transects, which consist of 520 units of 5 cm× 5 cm contiguous 45 microquadrats were used for beta diversity estimation. Two information theory models were 46 calculated the baseline transect data, in order to describing the fine-scale spatial structure of 47 each understorey community. The results showed significant differences (p≤ 0.05) between the 48 two types of understory vegetation functions and these parameters. Our result show, the native 49 conifer J. communis creates a more complex, highly organized microhabitats compared to the 50 invasive, P. nigra. Thus, can conclude that native conifer species has positive effect on the beta 51 diversity of understorey vegetation. Based on our study, the removal of the invasive woody 52 species is required in order to sustain diversity of these habitat and reducing the risk of the 53 introduction of other alien species. 54