The structure of the pungent principle spilanthol isolated from the aerial part of Spilanthes oleracea JACQUIN (Compositae) was elucidated as (2E, 6Z, 8E)-N-isobutyl-2, 6, 8-decatrienamide by comparing its proton and carbon-13 nuclear magnetic resonance spectra with those of all-trans spilanthol.