Various precooling treatments were applied to prolong the freshness of mibaek peaches that were harvested during the summer season. Peaches were cooled from $25.9^{circ}C$ to $5^{circ}C$ within 3 hours by a pressure cooler, and the cooling rate was accelerated by increasing the air velocity and static pressure. Respiration and ethylene production rates of mibaek peaches were about four times faster at $20^{circ}C$ than at $7^{circ}C$, while precooled peaches had better visual quality at $7^{circ}C$ than at $20^{circ}C$. Also, precooled peaches had higher soluble solid and ascorbic acid content than non-precooled peaches when stored at 7 and $20^{circ}C$. However, weight loss was lower in precooled peaches than in non-precooled peaches during storage.