Overall impregnation behaviors with vinyl monomers to some leaf and needle woods and their distribution in woods are described. Attention is directed toward the observations of both the monomer uniformity in wood and fluid flow by diffusion mechanism which is one of the important processes in practical impregnation treatments of bulk wood. Diffusivity is appeared to depend on the percentage of void, but the uniformity of fluids in wood is found to be promarily limited by the nature of fluid pathways. Leaf woods show their affinities to MMA, but pines have exhibited their preferences to styrene.