Many members of the Asparagaceae family are used in traditional medicine in different countries and characterized by a high content of biologically active metabolites. In this work, the qualitative composition and quantitative content of the components of methanol extracts from leaves and underground organs of Sansevieria cylindrica Bojer ex Hook, Sansevieria trifasciata Prain, Polianthes tuberosa L., leaves of Yucca filamentosa L. and Furcraea gigantea var. watsoniana (Hort. Sander) Drumm. were determined. Extraction of plant leaves and underground organs using 80% methanol resulted in 5.2–16.7% and 16–25.1% of the total extractive substances consequently. The presence of steroidal saponins in the extracts was shown by thin layer chromatography. Spirostanol saponins were predominate in the extracts from leaves of Y. filamentosa, F. gigantea and underground organs of S. cylindrica, S. trifasciata, P. tuberosa, furastanol saponins – in the extracts from leaves of S. cylindrica and S. trifasciata. The content of terpenoid and phenolic compounds in the extracts established using spectrophotometry significantly differs depending on the plant species and their anatomical part. All the extracts tested exhibited inhibition of the 2,2-diphenyl-1-picrylhydrazyl free radical in dose-dependent manner. The highest antiradical activity demonstrated the extract from the leaves of Y. filamentosa (IC50 = 25.95 μg/ml) containing the largest amount of phenolic compounds, including flavonoids – 51.3 and 15.5% of the total extractive substances.