As agriculture continues to be a major contributor to water pollution, climate change and loss of biodiversity in the EU, agro-environmental measures have been introduced to encourage conventional farmers to acquire more sustainable organic practices. This study analyzed the effect of different intensity farm management (conventional and organic) on variations of floristic diversity in crop fields (C) and non-production areas – uncropped field margins (UCM). The outcomes of the study can thus support the creation of a more diversified set of habitats and greater landscape heterogeneity. The main goal of this research was to evaluate and compare the impact of organic and conventional farming on plant diversity at a habitat scale (alpha-diversity). Assessments were carried out on differently anthropogenized agro-environment background (C and UCM) of organic and conventional agriculture at the Lithuanian University of Agriculture. It was observed that sustainable land use (OF) leads to preservation of biodiversity, which is the element of crucial importance for landscaping. Registered total plant diversity was represented by 127 species ranked in 21 plant families of Magnoliophyta (Angiopsermae) and 1 family of Equisetophyta, depending on farming type and habitat anthropogenic level. The field margins habitat of organic farming provide the maximal species diversity (71 sp.; 3.6 alpha-diversity index). Conventional farming management emerged as the negative impact on floristic diversity (2.1-2.9 alpha-diversity index) due to the intensive application of chemical fertilizers and various pesticides during plant vegetation.