Four new labdane-type diterpenoids: hedychicoronarin (1), peroxycoronarin D (2), 7 beta-hydroxycalcaratarin A (3), and (E)-7 beta-hydroxy-6-oxo-labda-8(17), 12-diene-15,16-dial (4), have been isolated from the rhizomes of Hedychium coronarium, together with 13 known compounds (5-17). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 3, 5, 6, and 10 exhibited inhibition (IC50 values <= 4.52 mu g/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 3-6, 10, and 11 inhibited fMLP/CB-induced elastase release with IC50 values <= 6.17 mu g/mL.