Saw dust concrete f3r finding out insulation characteristic was tested using test plate $30cm{ imes}30cm{ imes}5cm$. basically, molds f3r the test of compressive, tensile, normal without sawdust, $0.05\%,;0.1\%,;0.2\%,; 0.4\%,;0.6\%,;0.8\%,;1.0\%,;1.2\%,;1.4\%,;1.6\%,;1.5\%,;2.0\%$, mixing proportion. heat conductivity of the saw dust concrete mixed with the above proportion was taken in this study. Thermal conduction of normal concrete depends on mixing proportion strength aggregate character, water content. all these items are specified here in fables. $1.8\%~2.0\%$ saw-dust mising concrete shows as the faction as normal insulation material has its function. and the higher saw-dust mixing rate becomes, the thermal conduction becomes the less Then, the conclusions are that saw-dust using concrete has better insulation function than normal concrete.