Abstract: AIM　To study the chemiacal constituents of the rhizomes of Kaempferia galanga L. (Zingiberaceae). METHODS　Various chromatographic techniques were used to separate and purify. Their physico-chemical properties and spectral data were used to elucidate the structures. RESULTS　Six compounds were isolated from the hexane extract of K.galanga. Their structures were identified as marginatol (1), 8(14),15-sanderacopimaradiene-1α,9α-diol (2), 8(14),15-sanderacopimaradiene-1α,6β,9α-triol (3), germacrone (4), trans-ethyl p-methoxycinnamate (5) and n-pentadecane (6) on the basis of spectral data (IR, MS, ¹H-¹H, ¹³C-¹H NMR, NOEs and HMBC). CONCLUSION　Marginatol (1) is a new isopimarene diterpenoid and was elucidated as 8(14),15-isopimaradiene-6α-ol. Compounds 2, 3 and 4 were isolated for the first time from this plant.