From this study we realized that except for Diospyros mespyliformis and Afzelia africana sawdust, the hot water treatment improves the compatibility of sawdust with cement. Thus, the sawdust cement composites made from Tectona grandis, Pterocarpus eurinaceus and Isoberlina doka (species with the best compatibility indexes), present better mechanical resistances than composites made from other sawdust. The introduction of Sporobolus pyramidalis fibers in the manufacture of sawdust cement composites showed low compatibility indices and reduced their mechanical characteristics. Therefore, a special treatment to the vegetable fibers must be made and their introduction in the composites must be made in fine proportions.