A set of experimental system for the study on the root system-soil interaction for laboratory work was presented. This system consisted of the following apparatuses and associating techniques for operation; (1) a handy-type root box covered with a mirror sheet, (2) a pinboard which enabled sampling of the root system in the root box soil as it stood in the soil, (3) a piece of holed polyethylene sheet for handling during the sampling of the root system and preserving the root system without impairment and disarrangement after sampling, (4) a transmitted light box for taking photograph of the root system. Techniques associating with those apparatuses consisted of the soil filling up into the root box, supplying water to the root box, washing out the root system from soil, and staining the sampled root system.Distribution patterns of soil porosity and moisture, and daily changes of soil temperature in the root box soil, were determined. Our soil filling-up technique gave high reproducibility as well as uniform porosity distribution in the root box soil with small difference among the root boxes. No significant differences were found in the soil moisture content at a given depth of horizontal soil layer. When the root box was put into the trench, the soil temperature in the root box was closer to that of a natural soil profile than when it was placed on the ground. Upland rice and maize were grown in the root box placed in the trench. Root systems sampled showed considerably uniform profiles among triplicated plants for both species. These results demonstrate the significance of preparation and control techniques of soil environments for the study on root system-soil interaction.