This paper deals with determination of potential carcinogenic and inhibitory activity of 10 compounds isolated from the ethanolic extract of Lilium candidum L. perfonned by DC polarography. The series of investigated compounds consisted of two spirostanol saponins, two pyroline derivatives, jatropham and its glucoside, flavonol kaempferol, 2-fenylethyl-alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside, 2-phenylethylpalmitate and methylsuccinic acid. Carcinogenic, resp. mutagenic activity data for these compounds, with the exception of kaempferol, are not available in scientific literature. All tested compounds were reduced in N,N-dimethylformamide in one or two well defined steps. They also fonned a reversible complex with alpha-lipoic acid, a compound serving as an indicator of carcinogenic activity. The marginal diffuse current values of these complexes served as a criterion of a very low potential carcinogenicity. The inhibitory activity of isolates were studied in the presence of 12-O-tetradecanoylphorbol-13-acetate, a specific tumor promoter for an epidermal carcinogenesis, and in the presence of a polyaromatic substance 7,12-dimetylbenz(a)anthracene known as a carcinogen. The spirostanol saponins possessed the highest inhibitory activity >> 70%) and jatropham (66%). The inhibitory activity of jatropham glucoside was significantly lower (49%). Practically zero inhibitory activity was measured for the 2-phenylethylpalmitate and methylsuccinic acid.