From seeds of Strychnos nux-vomica three iridoids, 6'-O-acetylloganic acid, 4'-O-acetylloganic acid and 3'-O-acetylloganic acid were isolated together with two known iridoid glucosides, loganic acid and 7-O-acetylloganic acid. The structures of the compounds were established by ESI-MS and by 1D and 2D NMR spectroscopic methods.