Abandonment of the use of agricultural areas, especially low-production grass communities, and the related secondary succession of trees and shrubs, affects the transformation of the soil environment. The work focused on the impact of extensive sheep grazing on activity of dehydrogenases (DhA) and neutral phosphatase (PhA) and the resources of total organic carbon (TOC) and available phosphorus (Pav) in the soils of meadow habitats in eastern Poland. These habitats are located within the ecological network Natura 2000: PLH060018 Stawska Góra, PLH060035 Zachodniowołyńska Dolina Bugu, PLH060010 Kąty and the Nature Reserve “Kózki” (PLB140001 Dolina Dolnego Bugu and PLH140011 Ostoja Nadbużańska). Soil material was collected for three years, twice each year: before and after the grazing. In the soils of all the studied habitats, a beneficial effect of extensive sheep grazing on soil enzymatic activity and TOC and Pav content was noticed. A particular marked improvement was observed in the biochemical status of the soil in the study area where sheep grazing was continued since 2008. This confirms the hypothesis that free grazing of livestock has a positive impact on biodiversity and the condition of the soil environment of Natura 2000 habitats.