Medicinal and aromatic plants with allelopathic effect are a potential source of natural herbicides. The experiment was conducted in order to assess herbicidal potential of meadow sage (Salvia pratensis L.) on germination and growth of weed species velvetleaf (Abutilon theophrasti Med.) and common corn-cockle (Agrostemma githago L.). Water extracts from S. pratensis dry biomass in different concentrations were evaluated under controlled laboratory conditions in Petri dish bioassay. Herbicidal effect of S. pratensis extracts depended on the extract concentration and weed species. In general, higher concentrations of water extract showed greater negative effect on germination and growth parameters of weed seedlings. A. githago had greater sensitivity to S. pratensis extracts with reductions in germination and seedlings growth up to 100% in treatments with 7.5% and 10% extract concentrations. A. theophrasti germination was not affected by water extracts, however, substantial reductions of root and shoot length as well as fresh weight of seedlings were recorded. S. pratensis proved as promising plant species for further studies.