Chromatographic fractionation and chemical investigation of the methanolic extract of the fronds and rhizomes of Adiantum capillus-veneris L. (Pteridaceae), resulted in the isolation and identification of four compounds. The structures of the isolated compounds were elucidated using ESI-MS, 1D and 2D (COSY, HSQC and HMBC) NMR experiments, as well as by comparison with literature data. The isolated compounds were identified as; pinoresinol 4-O-β-d-glucopyranoside (1), pterosterone (2), kampferol-3-O-β-d-glucuronide (3), and quercetin-3-O-β-d-glucoside (4). Compounds 1 and 2 are reported here to be isolated for the first time from family Pteridaceae, however compounds 3 and 4 were isolated previously from the plant. Total methanolic extract as well as n-hexane, ethyl acetate (EtOAc) and n-butanol (n-BuOH) fractions of A. capillus-veneris L. fern were evaluated for their antidiabetic and anti-yeast activity. The four isolated compounds were also evaluated for their anti-yeast activity. The ethyl acetate fraction showed the highest antidiabetic activity. Its inhibitory activity against both α-glucosidase and α-amylase enzymes was with IC₅₀ values of 52.8 µg/ml and 62.4 µg/ml, respectively. The n-hexane fraction showed the highest anti-yeast activity.