For investigation of the optimum gas composition for CA storage of Shingo pear, the pears were kept at 8 different $O_2/CO_2$ concentrations for 5 months and checked in some indices related in storability and sensory quality after storage and transfer to air at $20^{circ}C$ for 1 week. The pears kept in all the CA storage conditions in this experiment, especially in $3%;O_2-3%,;CO_2$, were lower in weight loss than the pears kept in cold room. Immediately after storage decay rates of the pears stored at CA storage conditions except $3%;O_2-3%,;CO_2$ and $3%;O_2-4%,;CO_2$ were more serious than that of the pears stored at cold room, and the rates of the pears, especially stored at cold room, were rapidly increased by exposure to $20^{circ}C$ after storage. The highest soluble solid content and firmess were shown in the pears stored at the CA storage condition of $3%;O_2-3%,;CO_2$, and the pears stored at the conditions of $3%;O_2$ and $4%{sim}5%;CO_2$ had the highest acidity. In sensory evaluation the pears kept at the conditions of $3%O_2-3%$, 4% and 5% $CO_2$ maintained a good quality after storage and after storage and transfer to air at $20^{circ}C$ for 1 week.