It has been reported previously that the tropical wood-lignins, especially the hard wood-lignins showed much differences in comparison with the ordinary hard wood-lignins, that is the higher lignin content, the low methoxyl content and differences in UV- and IR-spectra as well as the low ratio of syringaldehyde to vanillin on alkaline nitrobenzene oxidation and thus, it was assumed that the structure of them would be similar to soft wood-lignins rather than hard wood-lignins.In order to further clarify the characteristics of tropical wood-lignins, the exhaustively extracted wood meals such as red lauan, white lauan and agathis sap woods with ethanol-benzene mixture, 95%-ethanol, hot water and acetone-water mixture respectively and the dioxane-lignins prepared from them were suffered from alkaline-treatment or NaBH4-reduction and compared with each other and with the ordinary wood-lignins namely beech, walnut and red pine sap wood.The same characteristics mentioned above were also supported in the investigations of extracted wood meals and dioxane-lignins.However, it was newly found that the presence of alkali easily soluble fraction in tropical hard wood-lignins and their contents amounted to about 10% of the wood and about 30% based on the Klason-lignin-content of the extracted wood.And also the residual lignins especially NaBH4-reduced dioxane-lignin showed essentially the same features as ordinary hard wood-lignins as shown in Table 15.In tropical soft wood, much differences would not be found but it was deduced that the similar things would also be occured. Thus, it was concluded that every characteristics on tropical wood-lignins reported earlier were caused by the presence of alkali easily soluble lignin fraction.