Panajaponin, a new glycosphingolipid compound (1), together with eight known compounds, 28-glu-oleanolic acid ester (2), chikusetsusaponin IVa (3), chikusetsusaponin IV (4), ginsenoside Ro (5), ginsenoside Re (6), notoginsenoside R2 (7), ginsenoside Rg2 (8) and adenosine (9), was isolated from Panax japonicus, and the structures of all of the compounds were established on the basis of NMR and MS spectra.