Three new guaiane-type sesquiterpenes named awabukinol, 4-hydroperoxyawabukinol and 3-hydroperoxyawabukinol, which are characterized by the presence of a hydroperoxy function, have been isolated from the wood of Viburnum awabuki. Their structures have been elucidated as (1α,5β,7β)-3,10(14)-guaiadien-11-ol, (1α,5β,7β)-4β-hydroperoxy-2,10(14)-guaiadien-11-ol and (1α,7β)-3β-hydroperoxy-4,10(14)-guaiadien-11-ol, respectively, by extensive analysis of spectroscopic data and some chemical transformations. The absolute configuration of awabukinol has been assigned as (1R), (5S) and (7R) on the basis of the CD octant rule applied to its 10-oxo-derivative.