Abstract: A kind of composite called wood-inorganic composite was produced by the method of double ions diffusion with fast growing Poplar wood, which is abundant in China, as the raw material and the ionic compound of silicon, aluminum, boron and phosphorous ions as the dipping solution. There were deposit reactions between the various kinds of ions in the walls and vessels of wood's cells. The wood's performance of decomposition in high temperature and strength were improved owing to water-fast deposits filling in holes of the wood. The results show that the performance of the wood is much more improved with the method of impregnating the solution into the wood by force by a self-made plus-minus pressure system compared to the method of impregnating the solution into the wood at normal press and temperature, and its WPG increases by 3~5 times. The SEM micrographs show that inorganic substance is filled not only in the vessels, fibers but also in the pits of the wood. The DTA Curve shows that the highest decomposition temperature of the treated wood is 420℃ and its loss percent of weight is 32 % at 550℃.In the research area,the strength of the treated wood is in positive proportion with the weight percent gain of the composites.