<jats:p>From the edible mushroom, the basidiomycetes <jats:italic>Agaricus bisporus</jats:italic> and <jats:italic>Agaricus campestris</jats:italic>, a novel carbohydrate‐homologous series of four glyco‐inositol‐phospho‐sphingolipids, designated basidiolipids, was isolated and the constituents purified. The chemical structures of the basidiolipids were elucidated to be: Man<jats:italic>p</jats:italic>β1‐2inositol1‐phospho‐ceramide, Gal<jats:italic>p</jats:italic>α‐6[Fuc<jats:italic>p</jats:italic>α‐2]Gal<jats:italic>p</jats:italic>β‐6Man<jats:italic>p</jats:italic>β‐2inositol1‐phospho‐ceramide, Gal<jats:italic>p</jats:italic>α‐6Gal<jats:italic>p</jats:italic>α‐6[Fuc<jats:italic>p</jats:italic>α‐2]Gal<jats:italic>p</jats:italic>β‐ 6Man<jats:italic>p</jats:italic>β‐2inositol1‐phospho‐ceramide and Gal<jats:italic>p</jats:italic>α‐6Gal<jats:italic>p</jats:italic>α‐6Gal<jats:italic>p</jats:italic>α‐6[Fuc<jats:italic>p</jats:italic>α‐2]Gal<jats:italic>p</jats:italic>β‐6Man<jats:italic>p</jats:italic>β‐2inositol1‐phospho‐ceramide. All four glycolipids contained a ceramide which was composed of phytosphingosine and predominantly α‐hydroxy‐behenic and α‐hydroxy‐lignoceric acid.