Ultrastructural changes in the chloroplast of apple fruits was examined with Malus Pumila Mill var. Fugi harvested during preclimacteric stage under the subatmospheric pressure storage condition at 380mmHg, 20℃. Electron micrographs obtained from the fruits stored at 760mmHg, 20℃ indicated that the initiation of ultrastructural changes is in parallel with the onset of respiratory climacteric. Chloroplast of the apple fruits stored for 25 days is vacuolated and the lamellar system are a little disorganized. Chloroplast of the apple fruits stored for 50 days is showing extensive vacuolation, the lamellar system are completely disorganized and the plasma membrane has pulled away from the cell wall. In the case of subatmospheric pressure storage caused to delay the onset of ultrastructural changes in chloroplast such as vacuolation, disorganization of lamellar system and dispersal of stroma lamella about 2 months. These results suggested that ripening of apple fruits is correlated not only to the activity of respiration but to the involvement of ultrastructural changes in fruit cells. The evidences obtained here led to the conclusion that subatmospheric pressure treatment extends storage life of apple fruits by inhibiting ultrastructural changes of cell organelles in concomitance with respiratory activity.