The purpose of this thesis is to build a dirt-walled house based on the principle of temperature/humidity control in the underground storage room and examine the constant temperature/humidistat effects. The result of the experiment showed that (1) the temperature inside the dirt-walled house was remained lower than the exterior temperature by 3.5-8 'C. And, the daily amount of temperature fluctuation turned out to be 2.5 - 5 'C, which was not significant. (2) The change rate of the humidity was maintained relatively steady at around 4 - 9%.