A natural ventilating type store was designed for the economic and effective storage of citrus fruits in Jejudo. The material used for the wall is scoria, widely distributed in Jejudo and known for high strength and insulation. Design condition was chosen for the period till March of a year and the dry bulb temperature was taken from TAC $5\%$ base. The temperature of the store can be maintained below the limiting temperature of $8^{circ}C$ for the time length of $7frac{1}{2}$ hours under the condition of the atmospheric temp, $15.3^{circ}C$ and the solar insolation. The limiting temperature can he recovered to the initial temperature $(7^{circ}C)$ by the natural ventilation for 8 hours in the night.