Self-prepared ethanolic and aqueous extracts and commercial tinctures derived from the herb of Alchemilla spec. and Potentilla anserina were compared for their antimutagenic potency using 2-nitrofluorene as standard mutagen. All samples studied showed weak or moderate activities. The total amount of tannins did not correlate well with the degree of inhibition. However, tannin-free extracts did not display any inhibition of mutagenicity. Therefore, the tannin fraction participates at least partly in the antimutagenicity of the extracts examined.